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David Kennedy writes with a review of Tom DeMarco's older Dorset House title, Why does software cost so much? (sub-title: And Other Puzzles of the Information Age.) Sounds like something to put in the same section of your library as Frederick Brooks Jr.'s The Mythical Man Month . Why Does Software Cost So Much? And other Puzzles of The Information Age author Tom DeMarco pages 230 publisher Dorset House rating 7 reviewer David Kennedy ISBN 093263334X summary An older collection of essays, some good, some bad, from one of the most respected names in the software management field.

Summary: An older collection of essays, some good, some bad, from one of the most respected names in the software management field. An interesting read, not least because of the amusement to be gained from how things have, and haven't, changed. Worth reading if you have the time, but not as essential as some of his other titles.

Check your sources. Tom DeMarco is an established industry figure who occupies that rarest of market niches - he's a management consultant/guru who has the respect of technical people. He's the co-author (with Tom Lister) of the classic "Peopleware" (which I suggest you rush out and read), and it's on the strength of that title that I read his work. I normally lack even the slightest interest in management titles, on the basis that Sturgeon's Law seems to be especially strict in that genre. For example, both my copies of "The 7 Habits of Highly Effective People" and "The Monk Who Sold His Ferrari" ended up in the bin. (If it helps, I have a library of about 5K books [mainly novels], and have only ever thrown out 4.)

What's this book about? This is a 1995 title, and as such is interesting for historical value. The blurb states:
"Drawing together several essays published previously, plus ten all-new papers never seen beyond his circle of colleagues, Tom DeMarco tackles a multitude of tough subjects and wrestles fresh insight out of them. Here's a compact, compelling edition of this acclaimed consultant's views of managing the software process."

What you get is 230 pages of essays or opinion pieces. There are 24 pieces, ranging from a couple of pages to a couple of dozen pages. A smattering of titles:

• Why does software cost so much?
• Management-aided software engineering
• Lean and mean
• If we did only one thing to improve...
• Software development: State of the art vs State of the practice
• Software productivity: The Covert Agenda

As the titles suggest, the focus is on software projects specifically, although much of the discussion re managing the effort could apply to many technical disciplines. All pieces which refer to surveys don't use numbers pulled from a hat, they use numbers pulled from the bibliography at the back.

Target audience It's a mix. Most of the pieces seem aimed at management, from team leader to project manager, but the discussion will be of interest to most programmers, especially those suffering from the Bad Management Blues, or who are thinking of taking a step sideways into a team lead role.

What's good? Quite a lot. This isn't a long book, and it's not going to revolutionize your life, but it makes for a decent couple of hours reading. The author can certainly write, with a chatty style obviously honed by a career based on presentations. All the pieces are easily digested, and usually contain a nugget of something interesting.

There are a few nice points in here re how and why you should manage your software project, but for me, the interesting thing about this older title is that it's a very different world he's talking about! For example, one piece, from 1989, talks about the difference between programmers working on identical tasks. They show nice charts and I was amazed to see PASCAL and BASIC in there. I expected to see COBOL of course, but the small size of the C wedge was shocking. Of course, there was no wedge for C++, let alone Java or Perl.

As with any older title, there are technological fossils like this to be marveled over in several essays, but it's quite interesting how the author pronouncements are generally, well, reasonable and right. He's not Nostradamus, and doesn't predict specifics, but there is a nice discussion on language uptake (he rails against FORTRAN and COBOL in a world of Modula-2, Oberon and SmallTalk! I suspect more people now now use the either of the former languages than all the latter languages put together). In this essay, he talks about how some of the third generation languages are wonderful, but suffer from inadequate or confusing libraries. He suggests that only wide and deep libraries really make people change languages in the real world. I know (from reading his new title, "Slack", review coming) that he's much further from the code now, but I wonder what he makes of Perl or Java? (Certainly the thing that lured me from C++ to Java was the libraries. Well, I missed the STL which makes the Collections API look like a child's homework.)

Other essays talk about the Microsoft anti-trust trial, or the fate of IBM. In both cases he seems to be more-or-less on the money, simply by being slightly cynical and not making any mad assumptions. Of course, by the same token, nothing he predicts is particularly startling, but still, of interest when reading.

There are a quite a few pages devoted to things which don't relate to technology specifically, and hence, don't appear dated now. These generally concern scheduling, or people management, and generally are as good as people expect this author to be. When he's good, he's very good. I want to work with a manager like him someday, just to see what it's like! However, even in these people-skills sections, I can't help but wonder what he'd revise in the light of the whole dot-con debacle.

What's bad? Well, this is a fix-up title, and some of the essays are, to be frank, crap. I doubt any but his most ardently completist fans want to read an essay on his experiences trying to work with desktop video for example. A couple of the essays just struck me as, well, rather pointless. Sometimes funny, but pointless. These tended to be the "Not previously published" ones, and I think there's a reason for that.

Alternate titles Oh, sure. There's a shelf full of titles like this in your nearest bookshop. I don't generally like any of them though, so I'll just recommend his earlier Peopleware and his latest, Slack.

You can purchase Why Does Software Cost So Much? from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

carambola5 asks: "Because we all know the world needs more inattentive drivers... I am a member of the champion UW-Madison FutureTruck team, which was the subject of this Slashdot report from June. Well, we're gearing up for next year and I'm on the sub-group that puts in all the cool interior stuff. Besides the Clarion joyride unit already in there, we're looking for other ideas (for example: a CF card that could act as both a key and remote access device for use in a handheld). What kind of little toys would you want in a car?"

dpbsmith asks: "It seems like a simple engineering problem--construct a device for easily and safely connecting several dozen wires at the same time--but the variety and creativity in their design over the years has been amazing, and, clearly there have been trends, fashions, and styles. In the fifties and sixties, virtually all connectors were roughly similar to the D-Sub design used for RS-232. A stiff, straight pin engaged a springy socket that contacted and bore against it on all sides. There were minor variations in shape and placement; the Amphenol Blue Ribbons (think Centronics), the connectors into which circuit boards engaged, but they were all variations on a theme. I was absolutely astounded the first time I saw a modular RJ-11 connector. Cheap, effective, and utterly unlike anything I'd ever seen before. Who invented these? Western Electric? Recently, we have the USB connector and the Firewire connector, obviously members of the same family (and a cheap-and-cheesy-seeming family it seems); on the other hand, my telephone and my digital camera have connectors that are very small and snap in with a positive lock that must be released with a squeeze, obviously yet another fundamentally different design. What do people know about the design, history, and engineering behind connectors over the years? Is it all hidden away, trade secrets of the connector companies, or is their a story that can be told?"

David Kennedy contributes the review below of Richard Hightower's new book Python Programming with the Java Class Libraries, subtitled A Tutorial for Building Web and Enterprise Applications with Jython, writing "This book tries to be suitable for both new and experienced programmers, and suffers from this decision. However, it presents all the central programming concepts clearly and is a decent primer on Jython. It is illustrated with copious code, and covers plenty of advanced topics. Worth reading if you're interesting in the Jython language. Oh, and ignore the sub-title." Python Programming with the Java Class Libraries author Richard Hightower pages 448 publisher Addison-Wesley rating B+ reviewer David Kennedy ISBN 0201616165 summary Solid technical primer on Jython. Probably best for those with some comp. sci. experience.

First Impressions We all know not to judge a book by its cover, but let's be honest; when looking at a bookshelf groaning with Learn ${technology} in 21 Days! and ${technology} for Utter Fools, it can be useful to have a filter to apply.

I have the following book-cover rules:

• Ignore everything with a cluttered cover. If I find the cover confusing, I doubt the content will be better.
• Look for an O'Reilly "animal" cover.
• Look for an "Addison-Wesley Professional Computing Series" cover. These tend to be white, with a blue stripe down the side, usually accented with magenta. C++ programmers especially should have several titles from this excellent series on their shelves.

Given my third rule, I am dismayed to see that Addison-Wesley have chosen to go with a cartoonish cover featuring a luminescent python constricting a brown sack marked "Java Beans." It's not the worst cover art I've ever seen, but I have to admit that I probably wouldn't have noticed it on the shelf. I know this seems like a minor criticism, but it is a crowded market.

Target audience So, who is this book targeted at? The blurb and publicity material make it clear that the volume has a split personality, seeking to satisfy both new programmers and experienced programmers.

I find this an odd decision, and while I can understand how it can be tempting to address both audiences at once, the end result feels more than a little fragmented. Let's have a look at the two cases.

If I was a new programmer, or was merely new to Python, would I choose this book over something more obviously targeted to me like the O'Reilly title, Learning Python (Mark Lutz and David Ascher)? I think I'd go with the O'Reilly title here if I was a novice, I mean, doesn't "building Web and Enterprise Applications" sound a little ambitious? Would a new programmer even understand the sub-title? (I've been working for over four years and I'm still not sure what exactly Enterprise is supposed to mean!)

Similarly, if I was an experienced programmer, perhaps in Java, would I pick up this book to get a handle on Python? Well, I might, but I might be dismayed at the amount of material on simple matters like if statements.

This is a pity, as the book probably works better for an experienced programmer, or at least one who has done some work in other languages. The sidebars are usually interesting and technically dense, delivering maximum information in limited space.

I think my main problem with the decision to deliberately split the readership into two target audiences is that I've seen it done better. For example, as mentioned above, Learning Python is probably the main competing title. It too addresses both the novice and experienced programmers, but does so in a much more transparent way. Rather than prefixing sections with "Advanced topic," thus alienating some readers, the more natural box-out approach is used. This gives a much less schizophrenic feel to the text, with the reader able to read the box-outs as and when they feel interested and able to understand the material. When reading Python Programming with ..., I sometimes felt like I was being directed in what to read.

I've been quite negative about this split up to this point, and would like to emphasize that the latter part of the book doesn't really suffer from this problem. Once assured that the new programmer has the basics under his belt, the text assumes a much more natural flow, with the standard optional box-outs. However, I should say that some of the material in the later chapters is non-trivial, and the smoother presentation of the more difficult material leads me to suggest that the author would have been better served by targeting the experienced programmer alone.

Let's look at the publicity blurb and contents in more detail:

" The goal of this 'first of its kind' book is to teach new programmers some of the basics of Python programming. Using skill-based exercises and interactive programming sessions, it helps new programmers develop an understanding of concepts and practical techniques. For experienced programmers, the book demonstrates Python's breadth of capabilities and demonstrates the ways that Python interfaces with the Java APIs for professional application development.

Topics include:

• Fundamental programming concepts, including statements, expressions, interpreters, and compilers.
• Python basics, including operators, string formatting, namespaces, classes, errors, and exceptions.
• Object-oriented programming concepts.
• File input/output.
• Python's intrinsic functions.
• Formatting, parsing, and manipulating strings.
• Interfacing with the Java APIs and working with Java Streams.
• Using Python and Java Swing to create GUIs.
• Working with SQL and JDBC.
• Python and Java applets."

This is a fair representation of the contents. As you can see the poor new programmer is soon expected to work with some non-trivial examples, with the streaming, database and applet sections all being welcome. The material presented particularly benefits from the fairly long example applications.

In addition, I feel that the appendices are interesting and worthy of mention.

• Installing Jython on Windows
• Installing Jython on Linux.

  Both installation guides are comprehensive and ensure that installation of the language itself shouldn't present any barrier to the novice, or those who are used to having a sysadmin install their work environment.

• The Power of Scripting.

  This is a nice section discussing the blurry distinction between programming and scripting languages, why you might want to script and use Java at the same time, what alternative languages are out there, and why the author feels Jython is interesting and useful.

• Java and Python: A Comparison

  This is an interesting section driving home why Jython is a nice alternative to Java for some applications. It presents some mini-applications, weighted towards Jython's end of the toolbox. They are a small GUI application, a statistics application and some string parsing.

• Regular Expressions.

  A decent workshop on Jython's regular expression facilities.

Oh Editor, where art thou?

I know that having a few mistakes is unavoidable, but there are a few howlers that slipped past the editing process. I particularly dislike this in an introductory book as it causes confusion in the reader and impedes his absorption of the material.

Some of the errors are typographical, and more than a few involve tabbing in code samples. Normally this would be merely irritating, but forgivable. Unfortunately, the significance of tabbing in Python makes this a much bigger problem for the novice reader!

There are also some properly editorial errors. As an example, the first time we see a user-defined function is in Chapter 4, on control flow. One of the canonical examples is wheeled out, a function to return (min, max, range) given a sequence of numbers.

This example is a nice one and is a good indication of why I generally like this book -- it has the user working with collections and mixed types right from the start, doesn't make a big deal out of defining a function, and includes a nice little box-out on efficiency. It also jumps right to a discussion on intrinsic operations and making sure to use them as they're more efficient and well-tested. It also blows up right after that, confusing the name of the argument list with the intrinsic function name and the name of the rewritten function. I wasn't able to untangle the paragraph until I saw the code. Bad editor, no treats!

So, is this book any good? Yes.

Python Programming with the Java Class Libraries is a well above average introduction to using Jython, best suited to interested readers already possessing some Java experience and a decent computer science background. It doesn't hesitate to tackle more complex topics, often with significant amounts of code (good thing), and the author demonstrates a wide knowledge of the field with many interesting box-outs often leading to further reading.

Readers completely new to the programming field will still find this book useful, but may well be intimidated by the advanced material scattered all over the first few chapters and the steep learning curve.

If that is the case, I would recommend that they stick with something like Learning Python should they wish to learn Python specifically, or any of the many other introductory texts on the market if they don't.

Those new to the field who choose to stick with this book will find that there is sufficient advanced material to ensure that the book remains valuable to them for some time to come.

Disclaimer There are two things I'd like to make clear:

• I did not pay for this book. I was given a review copy by the nice people at Addison-Wesley publishers. The author put my name on his list following a review of his previous title. This was decent of him as my previous review had some negative comments.
• I'm not a experienced Python developer. My background is C++ and J2EE. A more experienced Python user may have additional issues with the coding style presented. I did not feel particularly able to judge beyond the basics.

You can purchase Python Programming with the Java Class Libraries from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

Alicia (ad454) writes "A new sub-notebook was released in Japan today, the JVC InterLink Victor MP-XP7210, which is one of the smallest notebooks around in recent years that does not have a Transmeta emulation processor. It has a true Pentium-III 800MHz processor, weighs only 885 grams, and is only 225x152x28mm in size. It also comes with 256MB ram (384 max), 30 GB harddrive, 1024x600 TFT display, SoundBlaster Pro compatable audio, V90 56kbps fax/modem, 10/100 ethernet, USBx2, IEEE1394 (ilink/firewire), cardbus type 2 PCMCIA, and SD memory slot. You can get the specifications, which are in Japanese; you can use Alta Vista to translate it. A number of stores in Tokyo are selling it for (JPY)209,800. It would be interesting to hear what type of opensource Unix (NetBSD, Linux, etc.) and X-windows driver support exists for it. Although some may find the keyboard and screen too small, many of us find it quite useable, especially when compared to a PDA."

MaxVlast writes in that the The 1394 Trade Association has adopted the FireWire trademark, logo and symbol as a brand identity for the IEEE 1394 connection standard in a "no-fee license agreement" between 1394ta and Apple. Apple has also granted 1394ta the right to sub-license the FireWire Trademark for use on products, packaging and promotion of the standard.

BoomZilla writes "Brian Walker, the self styled "Rocket Guy" is making excellent progress with his one-man booster. Project R.U.S.H. plans to launch Brian in to orbit 'sometime later this year'. Brian's site (http://www.rocketguy.com/rocket.html) has many excellent pictures of the rocket and launch site (his backyard!) under construction. This is certainly the real (if somewhat dangerous) deal." (And Napkin Art? Look here.) Update: 05/29 04:08 GMT by T : Brian Walker dropped a note to point out that his plan is actually for a sub-orbital flight 35 miles up, not Earth orbit.

ScuzzMonkey asks: "I work for a small company trying to streamline some business processes in Washington State. As a part of this initiative, we're considering implementing a 'paperless' contracts system. In order for this to work out, on our end, we need a legally acceptable method of electronically signing the contract documents that we receive via fax from our sub-contractors (at this time, they will still be signing manually; this may eventually move to e-mail and digital signatures on their end as well as they become more capable of dealing with us on that level). On the face of it, this seems pretty straightforward. I set up some sort of certificate or some such for our employees responsible for signing these documents, and they simply review the TIFF attachment that comes in from the fax software and 'sign' it with their digital signature via a selected program. With the passage of the E-Sign Act (PDF) in 2000, it seems like this should be every bit as solid in court as a written signature. But while I've been able to find quite a lot of information on the web about the theoretical ramifications of this law, there's not much on practical implementations. What sort of software should I use? Do I need a third-party issued certificate? If so, do I just need one for the company, or one for each signer? What certificate authorities would you recommend? Do some certificates work with some software but not other software? What about this program from the state? Has anyone done this successfully yet? Any other stumbling blocks I should be aware of here, either legal or technological?"

HobbySpacer writes: "A serious market study has finally been done on space tourism and it shows a substantial market, even for brief sub-orbital flights. The Futron/Zogby study of high income individuals found that 19% would pay $100k for a sub-orbital flight. Furthermore, 7% would pay $20M to go to the Space Station (if they had the money.) The percentages go up if the prices could come down, especially with availability of private orbital facilities. With around 30 million high-net-worth households ($500,000+) in the US, this indicates a market of several million for suborbital on the short term and eventually for orbital. We can hope that like previous expensive luxuries, e.g. jet travel and ocean cruises, the wealthy will pull the prices down to a level reachable by the rest of us."

According to this press release and this article from The Register , AMD has leveraged the technology portfolio of recently acquired Alchemy Semiconductor to introduce an ultra-low-power processor designed for sub-PC applications. The chip is based on the Alchemy Au1 core and features, among other things, an integrated LCD controller and a pair of Secure Digital controllers.

jhiv writes: "The Delaware Aqueduct, one of the world's longest water tunnels, may be developing potential serious leaks, according to this article in the New York Times (free registration). One leak has already created a pond and a stream with a flow of a million gallons per day. New York city officials plan to use a robotic mini-submarine being developed by the Woods Hole Oceanographic Institution to inspect the interior of the 13 foot diameter tunnel. Previous repairs required four deep sea divers to spend almost a week at 700 feet pressure to fix a leaking valve. Ironically, if the tunnel is repaired, the wetlands created by leaks will be destroyed, causing a potential EPA violation. Additional coverage can be found here and here." NYC has been building a third major water tunnel to take the load off the first two - but it's a fifty-year project.

An anonymous reader writes "Pan Am might be gone and there isn't a Hilton in space yet, but you will soon be able to use your frequent flyer miles to at least come close to the final frontier. This article on SpaceRef.com details a new Space Adventures and US Airways partnership, where US Airways dividend miles may be cashed in for Space Adventures programs, most notably their sub-orbital flights that are expected to begin by 2005. Cost: only 10,000,000 miles. More reasonable totals can get you a zero-g parabolic flight, or a Mach 2.5 flight on a MiG-25. Space Adventures is the outfit that's been arranging trips to the ISS. One small problem though, is that they don't actually have a sub-orbital craft yet."

John Q is contemporary Hollywood's idea of an issue movie: preachiness hiding behind a superstar. The good news is that a major film studio is taking up a complex issue like health care, one of the worst messes in American life. The bad news is that the movie is so hypocritical, heavy-handed and gummed up with silly, sentimental and cliche-stuffed sub-plots that it undermines its own good intentions. Fortunately for the studio, Denzel Washington and Robert Duvall are always worth seeing. Spoilage warning: plot is discussed, not ending. And your own reviews are as welcome as mine.

The plot is pretty simple. Denzel Washington plays John Quincy Archibald, a beleaguered working class guy in Chicago whose hours at the factory have been reduced and whose car has just been repo'd. He is catching guff about money from his wife (Denise Archibald), and the couple has a cute and loving kid Mike (Daniel Smith) who collapses during a baseball game.

It turns out that Mike needs a heart transplant, which the nasty hospital administrator (Anne Heche) informs John will cost $250,000, an operation his insurance policy doesn't come close to covering. The Archibald's sell of nearly everything they own to try and raise the money to pay the hospital and the greedy, uncaring surgeon (James Woods) and as Mike slips closer to dying, John snaps and takes over the hospital emergency room.

Robert Duvall plays Lt. Frank Grimes, an aging hostage negotiator undermined by his idiot boss (Ray Liotta). Almost everybody in this movie is a cliche -- the uncaring administrator, the political and bumbling police chief, the saintly, too-good-to-be true John Archibald, whose solution to his very valid complaints about the American health care system -- a solution much endorsed by the movie -- is to get a gun and take over the emergency room while patients bleed and give birth. Even while holding hostages at gunpoint, Washington's character is noble, even saintly. Washington is a great actor and he is a likeable hero here, but the plot just takes too many loopy twists and turns. Everyone in the film is either a cartoon villain or a noble lifesaver really to preach about the evils of HMOs at the drop of a gun.

The best parts of the movie, not surprisingly, occur when Duvall and Washington are sparking off one another. But unaccountably, there are so many silly plot contortions that the power of that great pairing is lost. Director Nick Cassavetes and writer James Kearns twist their movie into a pretzel trying to deal with all of the potential racial, class and political sensibilities. To balance all the evil doctors, there are some wonderful ones.

To avoid the appearance of hitting racial issues too hard, Archibald's friends are all white. In addition to the stupid police chief (is any authority figure in America ever competent in a Hollywood movie?), there's a woman-beater and an airhead, vain TV reporter.

I won't give away the ending, but it's fun watching the moviemakers wrestle with a dilemma of their own making. The movie seems to be saying that the best way to deal with your insurer is to get a weapon and take some hostages. Unlike the heroes of Dog Day Afternoon, perhaps the classic modern hostage movie, John Archibald is saintly and noble enough to run for President. So what becomes of our Dad/kidnapper? You'll have to see the movie to find out. It's entertaining, and it's almost sure to be a big hit. But even a superstar can't mask a silly story.

Thomas Colthurst writes "You've no doubt already read the story of ping, but have you ever used it to measure the speed of light?" Here's a case where all that cat5 on college campuses can actually be used for education ;)

jonr asks: "After I got my Olympus E-100RS camera, I have been enjoying photography again. I now take on average dozens photos a day. Now the problem is ever growing photo collection. I found an excellent archiving software, IMatch but I'm looking for something similar to run under Linux. Folders and sub-folders are are just not cutting it. IMatch allows me to put my photos in a category tree, e.g. a photo of my dog could be placed in Family/Pets and Animals/Dogs. It also has off-line archiving, a must have for growing collection. Now does anybody know of a tool or a collection of tools for this?"

tepes writes "From bottomquark, A new method of sub-pixel rendering could make monitors cheaper to produce. ClairVoyante Laboratories developed the PenTile Matrix, which uses five sub-pixels instead of the typical three, to take advantage of the fact that the human eye is more sensitive to blue colors."

CodeShark writes: "According to this story at CNN, Transmeta is set to release their new TM6000 microprocessor this afternoon. The chip apparently incorporates some of the functions usually provided by high-performance (and high price!) chip sets. Transmeta is reporting a further reduction in power requirements by 44% and sees the laptop and sub-laptop markert as the primary markets for their new CPU. Intel and AMD claim to be catching up with the Transmeta chips in terms of power requirements, I'd be curious to find out what the real world comparisons might make of those claims ..." If anyone out there is at Microprocessor Forum, please say in comments any further details that are made clear there.

HobbySpacer writes: "XCOR announced the success of the first phase of flight tests for the EZ-Rocket. In the most recent flight, Dick Rutan fired both of its rocket engines to take off and reach a speed of 160knots and an altitude of 6200 feet. The vehicle is a Long-EZ kit plane modified to hold twin 400 lb thrust rocket engines fueled by isopropyl alcohol and liquid oxygen. The project is not aimed at a homebuilt EZ-Rocket but will demonstrate safe and reliable rocket propulsion. The primary goal is development of reusable launch technology that leads next to a high altitude sub-orbital rocket vehicle for space tourism, rocket racing (e.g. vertical drag racing at air shows) and the X-Prize competition."

DrRobin asks: "For the past couple of years, some of the techie parents in my town (Needham, MA) have been giving talks for parents of local elementary schools about online kid/family safety. I know there are a lot of weighty issues here in general but I want to ask if people here have any specific thoughts about the sub-topic I am supposed to cover: viruses (and worms, trojans, etc.). The parents are pretty sharp in general but not necessarily clued in to the net world. I have been on the net since '83 but my principal expertise is the little bitty wetware viruses that make you ill, rather than the software kind that infect computers. Any pointers people think would be helpful to parents would be appreciated."

What the Internet is really for, explains one sage in Jay and Silent Bob Strike Back, the latest in Kevin Smith's continuing series featuring the two drug-dealing, sex-obsessed slobs from central New Jersey, is so kids can slander other people anonymously. In his previous movies -- Dogma, Chasing Amy, Clerks -- Smith chronicles work, sex and blasphemy. This time the sub-theme is the Net and the waves of brainy but obnoxious adolescent jerks who have helped set its sometimes nasty tone in recent years. Many readers of this website will especially love the ending, one of the few Hollywood got right this summer. Spoilage warning: plot is discussed, but not ending.

In a way, Jay and Silent Bob Strike Back is a series of inside jokes, albeit some very funny ones. Smith gets that movies are a universal experience of his young audiences. Still, only attentive, die-hard movie buffs will get them all. The cast, plots and references are closely tied to other Smith films, lines, scenes, actors and plots, along with some that aren't his. (There is a hilarious spoof of Good Will Hunting which Ben Affleck and Matt Damon good-naturedly join in.) Smith's studio Miramax is continuously ridiculed (Bob Hope also used to poke fun at Paramount in some of his road-trip comedies with Bing Crosby). Chris Rock pops up with some riffs on race.

The movie's director, Gus Van Sant (CT:Good Will Hunting, not J&SBSB of course), has a funny bit part, and Smith parodies Charlie's Angels, The Fugitive (so specifically he includes a reference to Provasic, the drug that nearly destroyed Richard Kimble's life), Scooby-Doo,Hannibal, and even Star Wars (Carrie Fisher and Mark Hamill appear, the latter in a loopy take-off on the mythic brawl between Darth and Luke.

The Net figures heavily in this sometimes hilarious if uneven movie, yet another comedy that self-referentially uses pop culture as humor, reference point and plot line. Jay (Jason Mewes) and Silent Bob (Smith) are outraged to learn that kids online are flaming the movie based on the comic book -- Bluntman and The Chronic -- that the pair inspired. Besides, they're not getting a dime out of any of it. Jay, who's never even heard of the Net, is astonished to learn that people can call you names online, and he flames them back, urging them to lick his private parts. He and Bob set out for Hollywood to stop the movie's production and end the besmirching of their alleged reputations. They have various misadventures along the way, including dust-ups with a nun, the Utah State Police, animal rights activists, federal wildlife officials, and nasty child geeks.

There is, of course, the inevitable moment when Bob speaks -- as always, finally provoked by the genial stupidity and crudity of his "hetero-life mate" Jay. This movie backs off from the controversial religion-bashing of Dogma, which triggered some boycotts and threats on Smith and the movie's producers. If the movie is frequently gross in the now-standard scatalogical way of studio films aimed at the hip and the young, it is good-natured and easy-going, not even remotely controversial. Jay is still obsessed with getting laid and with his and everybody else's masculinity, but this round is much more relaxed about it.

Jay and Silent Bob Strike Back is less of a coherent movie than a series of one-liners, set gags, set-ups and cultural in-jokes and spoofs. There are moments of genius and of stupidity, also flashes of satire and comic genius. It works best if you've seen a substantial chunk of the Smith canon. If you haven't, a lot of it will sail over your head. But it will still probably be the funniest movie you've seen all summer.