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dirk and a large number of other distressed readers let us know that Apple is shuttering Lala, the music service they bought last December, on May 31. "Apple will transfer any remaining money in a user's account to iTunes, and will credit users (via iTunes) for any web songs that were purchased. It's a real shame, as Lala was a much better music service, offering songs in straight MP3 format. Its web service was innovative and ahead of its time. And it was one of the few places that would let you listen to an entire song to sample it (after one complete listen, you then could only hear a 30-second sample)." Reader Dhandforth adds: "10-cent favorites will now cost 9.9x more. What's worse, a community of music fans (followers and followees) will disappear on May 31. Evil. Sigh."

Vigile writes "Few people will doubt that PC gaming is in need of a significant shot in the arm with the consistent encroachment of consoles and their dominating hold on developers. Today AMD is releasing the Radeon HD 5870 graphics card based on the Evergreen-series of GPUs first demonstrated in June. Besides offering best-in-class performance for a single-GPU graphics board, the new card is easily the most power efficient in terms of idle power consumption and performance per watt. Not only that, but AMD has introduced new features that could help keep PC gaming in the spotlight, including the first DirectX 11 implementation and a very impressive multi-monitor gaming technology, Eyefinity, which we discussed earlier this month. The review at PC Perspective includes the full gamut of gaming benchmarks in both single- and dual-GPU configurations as well as videos of Eyefinity running on three 30" displays."

Vigile writes "Last year a small company called Lucid promised us GPU scaling across multiple GPU generations with near-linear performance gains without restrictions of SLI or CrossFire. The company has been silent for some time, but now it is not only ready to demonstrate the 2nd generation hardware, but also to show the first retail product that will be available with HYDRA technology. In this article there is a quick look at the MSI 'Big Bang' motherboard that sports the P55 chipset and HYDRA chip and also shows some demos of AMD HD 4890 and NVIDIA GTX 260 graphics cards working together for game rendering. Truly platform-independent GPU scaling is nearly here and the flexibility it will offer gamers could be impressive."

iCharles writes "According to this SEC filing per this Palm Infocenter story, it would appear that Palm is spinning off its OS devision. I'm a Handspring user, so it sounds quite interesting to me."

gizmo_mathboy writes: "Yahoo! Dailynews has the following Space.com article about the risk of using aerobraking for orbital insertion of spacecraft versus the certainty of using conventional propulsion systems. This is all explained in terms of the Mars Global Surveyor craft that is expected to do its orbital insertion on October 23. Skip the wimpy aerobraking and as a prophead trapped in a code monkey's job I say, "In Thrust We Trust.""

gizmo_mathboy writes: "General Software has announced the fastest BIOS boot time on record. The embedded system was clocked at 0.8 seconds from system power-on to transfer of control to LILO. This was on an Intel SOYO motherboard (440BX chipset) running a PIII 400. I think the quote of the article is: 'This Embedded BIOS quick-boot operation allows the device to restart and resume operations well within three seconds -- the maximum amount of downtime allowed per year for a device that must support "seven nines" or 99.99999 percent uptime.'"

gizmo_mathboy writes "Roger Ebert has an interesting commentary on Yahoo!'s recent decisions concerning porn on their site. Who says that a few people can't change a company?"

gizmo_mathboy writes: "The 9th Circuit Court has ruled that not being able to type does not give one protection/privilege under the Americans with Disabilities Act(ADA). This article on Yahoo! has information concerning the case."

Jim Bumgardner took it upon himself to review two of the major Legos Mindstorms books out on the market. The first, O'Reilly's The Unofficial Guide to LEGO MINDSTORMS Robots, has been reviewed here before, but this review adds a comparsion to the second book. The second is from Apress Press, and is titled Dave Baum's Definitive Guide to LEGO Mindstorms (Technology In Action). Click below to learn how to use your Mindstorms more effectively. The Unofficial Guide to LEGO MINDSTORMS Robots & Dave Baum's De author Jonathan B. Knudsen & Dave Baum pages 266 publisher O'Reilly & Apress rating 8/10 reviewer Jim Bumgardner ISBN 1-56592-692-7 & 1-89 summary A broader overview of the Lego Mindstorms world, with coverage of alternativefirmware and building your own sensors. & An in-depth look at building and programming Lego Mindstorms Robots, witha particular emphasis on robot design and NQC programming. An Embarrassment of Lego (books) As you know, this year's best holiday gift for the important geek in your life is a Lego Mindstorms Robotic Invention System (RIS). Through strategic use of heavy-handed hinting, I managed to get my loved ones to purchase one for me a few weeks ago for my birthday. I've been obsessed with the thing ever since, and recently picked up copies of the two available books on the subject, which I'll compare for you below. Knudsen's book was reviewed here recently, while Baum's has not.

Since Robotics involves a lot of different disciplines, these books are going to have a pretty varied audience. In my case, I'm a longtime programmer and (extremely) novice robot builder who couldn't properly handle a soldering iron if my life depended on it. I'm not particularly interested in the chapters on the ins and outs of the C language, but very interested in things like gear ratios and sensing algorithms, which I never learned in school. The mileage you'll get out of these books will vary, depending on your background.

In the comparitive sections below, Knudsen's book (and Knudsen himself) will be referred to as K, while Baum's book (and Baum himself) will be referred to as B.

Cover First let's get the important stuff out of the way... K's cover is prettier, having a picture of a cute bunny wobot. It's an O'Reilly book after all.

Length B is 34 pages longer, but K uses a smaller font. I suspect B is a bit longer, but not by much.

Value Both are 25 bucks retail, and cheaper online (typically 20 bucks). B comes with a CD-ROM. K doesn't. The CD contains all the sample code, a copy of NQC and related utilities, some demos and a QuickTime movie showing the assembly of one of the simpler robots (tankbot). With the exception of the sample code, the CD-ROM is kind of superfluous.

Illustrations K uses photos, which have been tweaked in Photoshop to remove the backgrounds. B uses computer-generated models rendered in isometric projection (also known as "2 1/2 D" -- similar to what you see in the Lego Constructopedia). Both books' images are reproduced in B&W and suffer for it. It's particular hard to see (and count) the holes in black beams, for example.

B's illustrations are definitely clearer than K's, primarily due to the use of computer graphics. The isometric projection definitely helps in figuring out how pieces fit together. K's illustrations have helpful lists of pieces and arrows showing where they go, however there are problems due to poor constrast and fuzziness, as well as distortions introduced by the camera's perspective. Despite these problems, I managed to get even his most complex bot, Minerva, assembled relatively quickly.

Breadth and Depth In general, K has more breadth, while B has more depth. K's book includes more introductory material about robotics (e.g. "What is a Robot?"), while B jumps right into installation instructoins, assuming you know that stuff already (e.g. "Robotics is nothing new"). K covers a lot of ground, including various available software packages, such as pbForth and LegOS, while B sticks to RCX code and NQC. K also gets into some interesting topics not found in B such as Subsumption Architecture and building your own sensors. On the other hand, B gets much more in depth into specific programming and modelling issues. There are a lot more examples of algorithms for handling touch and light sensors, and discussion of specific problems that might arise and how to deal with them. B's line following algorithms are different, taking advantage of the percieved "gray area" on the edge of the black line, using upper and lower feedback limits, while K uses a "zig-zag" approach with a single threshhold value (when I implemented them, I found K's approach to be more effective - the "gray area" approach requires more minute adjustments). B also has good coverage of the strengths and weaknesses of the different mindstorm kits and parts.

Programming B coverage of algorithms is generally better, particular in his detailed handling of touch and light sensor issues. K has a nice example of Rodney Brooks' subsumption architecture, written in NQC.

B, being the author of NQC, makes NQC programming an intregal part of his book. Every program is shown in both RCX Code and NQC versions (although the RCX Code version is often seriously crippled (as needs be). Nonetheless, B appears to have more success in getting RCX Code to do useful things than K, who pretty much gives up on RCX Code after a couple of chapters. A personal note: I found RCX Code to be a general pain in the ass. Personally I'm not all that convinced that it is a better alternative for the novices it is aimed at. Especially when you have to go though such contortions to to get it to do such useful things. Is mouse pushing really all that simpler than typing?

Design Both books cover design reasonably well. I'd give the slight edge to B, who has a good design chapter before going into the specifics of building individual robots. The chapter not only covers some of the things covered in Fred Martin's "Art of Lego Design" paper, but also covers the use of Pulleys and Ratchets. K tends to weave similar design lessons directly into the chapters on specific bots. There are design issues in both books not covered by the other. B's discussion of stresses in bumpers is quite good. K has some nice examples of directional transmissions (which don't necessarily use the differential).

Robot Models Both writers' basic robots, are simpler and more utilitarian than their Lego counterparts from the RIS's Constructopedia, which tend to be a bit more fanciful (although K uses the all important wings parts for Minerva). Both books start with a basic tread robot which make ideal learning tools for learning to program with touch and light sensors. K's robot is geared down right away (for more power and lower speed). B doesn't gear down until the reduced speed is needed (for line following). B's book has designs and programs for 14 different robots, some mobile, some not. K only has 4 robots (all mobile robots). Both of these numbers are misleadingly high, since some of the bots are quite similar. Some of B's more advanced bots require extra parts not included in the RIS kit. In some cases, the extra parts are needed to explain an interesting concept, like rack and pinion steering. B includes some designs for some interesting non-mobile robots, such as a brick sorter and a vending machine, which reads lego "punch cards". Both books' final robot is an armed robot - apparently the holy grail of many robot designers (there's one depicted on the cover of the RIS kit which I'm guessing can't be built with the stock parts). B's robot, RoboArm, requires an extra motor and bricks. K's robot, Minerva, manages to do a lot of stuff using all stock parts from a single 1.0 RIS kit (he accomplishes this via a directional transmission and an ingenious one-motor grabber arm borrowed from Ben Williamson). When I built this model using my 1.5 kit (which has a slightly different allotment of pieces), I found I was missing a couple bevel gears needed to complete the model (I borrowed some old style "thin" bevel gears from my daughter's Lego bucket, but they're very flimsy). This bot certainly accomplishes a lot with relatively spare resources, although it is perhaps pushing the envelope too far, as the "arm" assembly tends to require frequent attention, as the author notes. I found it useful to test more advanced designs with a spare 9V battery box I had left over from an old Technic kit. You can also use your computer as a remote, for this purpose.

Online References K's online references are more thorough. Both books have the most important URL, of course, which is www.lugnet.com - the center of the online Lego universe.

Timeliness B, a little later to press, includes coverage of RIS 1.5, and differences between RIS 1.5 and 1.0 (they are relatively minor).

Writing Style K tends to wax a bit more eloquently. I like his prose better. B is a bit less philosophical and tends to dive right into discussions of procedures and problems. This has its merits too, as he devotes a little more time to the nitty gritty.

Conclusions In some ways, these books are a little bit superfluous. The whole point, it seems, of the Lego Mindstorms kits is to learn by doing - by playing with them. Also, a lot of the material in the books, such as coverage of NQC, LegOS and other software packages, can be easily found on the net. Nonetheless, I found myself compelled to suck up both books, and I'm sure I will ultimately use some of the tips and tricks I've learned from both.

The two books complement each other very well, and if you have the interest and the bucks, I would spring for both. Knudsen's book provides a broader overview of the Lego Mindstorm's world and robotics in general, while Baum provides a lot of valuable technical information on solving specific problems. Purchase The Unofficial Guide at fatbrain or grab Dave Baum's at from fatbrain as well.

Table of Contents (Baum)

• Preface
• Introduction
• History

• Part I-Building Fundamentals
  • Chapter 1 - Mechanics
  • Chapter 2 - Motors
  • Chapter 3 - Sensors
  • Chapter 4 - Basic Vehicles
• Part II-Programming Fundamentals
  • Chapter 5 -NQC
  • Chapter 6 - Robolab
  • Chapter 7 - Sequenced Operations
  • Chapter 8 - Event Based Programming
  • Chapter 9 - Making Decisions
  • Chapter 10 - Using Feedback
  • Chapter 11 - Data Logging
  • Chapter 12 - Using more than one RCX
  • Chapter 13 - Advanced Programming
• Part III-Robots
  • Chapter 14 - Garbage Truck
  • Chapter 15 - Copy Machine
  • Chapter 16 - Vending Machine (or ATM)
  • Chapter 17 - Robot Tag
  • Chapter 18 - Elevator
  • Chapter 19 - Brick Sorter
  • Chapter 20 - Electric Train Controller
  • Chapter 21 - Stair Climbing/Walking
  • Chapter 22 - Multiple-RCX Robot
  • Appendices
    • Appendix A. Other Resources
    • Appendix B. On-line Resources
    • Appendix C. Robolab Development Environment
    • Appendix D. Lego CyberMaster product
  Table of Contents (Knudsen)
  • Preface
    
  1. Welcome to MINDSTORMS
     • What Is a Robot?
     • Mobile Robots
     • What Is MINDSTORMS?
     • What Now?
     • Online Resources
  2. Hank, the Bumper Tank
     • About the Building Instructions
     • Building Instructions
     • A Simple Program
     • Wheels
     • Bumpers and Feelers
     • Gears
     • Multitasking
     • Online Resources
  3. Trusty, a Line Follower
     • Building Instructions
     • Some Tricky Programming
     • The Light Sensor
     • Idler Wheels
     • Using Two Light Sensors
     • Online Resources
  4. Not Quite C
     • A Quick Start
     • RCX Software Architecture
     • NQC Overview
     • Trusty Revisited
     • Online Resources
  5. Minerva, a Robot with an Arm
     • Building Instructions
     • Programming
     • Directional Transmission
     • Pulleys
     • Mechanical Design
     • Two Sensors, One Input
     • Where Am I?
     • Online Resources
  6. pbFORTH
     • Replacement Firmware
     • pbFORTH Overview
     • About Forth
     • pbFORTH Words
     • An Expensive Thermometer
     • Minerva Revisited
     • Debugging
     • Online Resources
  7. A Remote Control for Minerva
     • Two Heads Are Better Than One
     • The Allure of Telerobotics
     • Building Instructions
     • Programming the Remote Control
     • Programming Minerva
     • Online Resources
  8. Using Spirit:ocx with Visual Basic
     • You May Already Have Visual Basic
     • About Spirit:ocx
     • Calling Spirit:ocx Functions
     • Immediate and Delayed Gratif ication
     • Programs, Tasks, and Subroutines
     • Tips
     • Retrieving the Datalog
     • Online Resources
  9. RoboTag, a Game for Two Robots
     • Building Instructions
     • Subsumption Architecture
     • Online Resources
  10. legOS
      • About legOS
      • Development Tools
      • Hello, legOS
      • Function Reference
      • New Brains for Hank
      • Development Tips
      • Online Resources
  11. Make Your Own Sensors
      • Mounting
      • Passive Sensors
      • Powered Sensors
      • Touch Multiplexer
      • Other Neat Ideas
      • What About Actuators?
      • Online Resources
  • A: Finding Parts and Programming Environments
    
  • B: A pbFORTH Downloader
    
  • C: Future Directions
    

Mitchell Baker, Chief Lizard Wrangler for Mozilla, has denied that Mozilla's development model will change. In related news, nullspace wrote in about netomat, a new "non-linear browser". "It bucks the trends of current browsers by mining random visuals and snippets of sentences from the Web and having it float endlessly across a black backdrop, accompanied by clips of sound, if the user desires. Users can specify a topic, then retrieve text, images, and/or audio from the Internet on the subject. They navigate by typing keywords into the browser, not by pointing and clicking."

An anonymous reader sent us a link to a startling article where you can read the horrific account of Linux Users Rioting Outside Microsoft's Silicon Valley Headquarters. The article shows graphic pictures of Linux Users being dragged off by the police, as well as burning of MSN CDs. I thought such violence was limited to Mighigan State basketball fans.

slim sent us linkage to a detailed guide to installing Linux on an iMac. " There are comments about LinuxPPC R4 and R5, but its come a long way. If those iMacs were a few hundred bucks cheaper I still think they'd be fun thinnish linux workstations. And the pretty colors.

Samus writes "The Golotha source has been mirrored on several ftp and web sites. Goto the mirror listing. Also a team of people is being formed to finish Golgotha. See the news article at Linux Games to join the mailing list. "

Chris Saylor writes "David Chun, a student from UCLA, called a dozen PC manufacturers asking if he could buy a PC without buying Microsoft Windows. " You can read results of the survey. I've recently recieved a few contradicting emails about Dell's rumored status on this adventure, and this page confirms that Dell does not offer any option in this department.

Jamie Zawinksi wrote in to tell me to tell everyone to lay off Mozilla.org and try one of the many mirrors- the huge demand has crippled the machine. Hit the link below to get a decent list of com and edu mirrors. Update:Couple of neato things, A screenshot of NS5 was sent in by Christopher Blizzard, and an insider who requested anonymity sent us a picture from this mornings big event, wrote "The main three people in this picture are Jim Barksdale, Jamie, and Tara Hernandez. Tara is manager of the build team. Just to the left of JimB is Jim Roskind, who led the Java-ectomy." Thanks guys.

ftp://odin.appliedtheory.com/pub/mirrors/mozilla/

http://www.gbnet.net/public/mozilla/

ftp://ftp.landfield.com/mozilla/

ftp://ftp.epix.net/pub/mozilla/

ftp://netscape.primehost.com/pub/ftp.mozilla.org/

ftp://wuarchive.wustl.edu/packages/www/mozilla/

ftp://ftp.muc.muohio.edu/pub/mozilla/

ftp://ftp.bogalusa.com/mozilla/

ftp://sod.off.net:211/pub/mozilla/

ftp://mirrors.javanet.net/pub/mirrors/mozilla/

ftp://ftp.tux.org/pub/net/mozilla/

ftp://ftp.cache-world.com/mirror/mozilla.org/

ftp://ftp.dqc.org/pub/

ftp://powermike.com/powermike.com/pub/ftp.mozilla.org

ftp://ftp.tos.net/pub/ftp.mozilla.org/

ftp://pfaffben.user.msu.edu/mozilla/

ftp://ftp.shuttle.org/mozilla/

ftp://mirror.neosoft.com/pub/mozilla/

http://www.us.inside.net/mozilla/

ftp://ftp.cise.ufl.edu/pub/mozilla/

http://sunsite.utk.edu/ftp/netscape-source/

ftp://mirror.tummy.com/pub/mozilla/

ftp://ftp.one.net/pub/mozilla/

ftp://ftp.mindwell.com/pub/mirrors/mozilla/

ftp://ftp.ntr.net/pub/mozilla/

ftp://ftp-netscape.connectnet.com/pub/netscape/source/

ftp://mozilla.meer.net/mozilla/

ftp://ftp.inetdev.org/mirrors/mozilla/

ftp://ftp.yggdrasil.com/mirrors/site/ftp.mozilla.org/pub/

ftp://mozilla.savages.com/

ftp://mirrors.xmission.com/mozilla/

ftp://ftp.dsnet.net/pub/