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I build a lot of stuff.
It's easy to make a coilgun. You take a cardboard tube, like wrapping paper comes on, fill it with 1/8" welding rod of various lengths so it's solidly packed at the bottom and only maybe 1/3 get all the way to the top. You wrap an *enormous* bundle of transformer wire around the base, where the rods are solidly packed -- like 400 turns of 18 ga wire. You point it upwards, and put a ring (best if aluminum, okay if copper, so-so if steel) around the tube and slide it down to the bottom. Then briefly plug the coil into the wall. The ring will shoot off the end like a gun. For extra credit, use a 2N2222 transistor driving the coil of a big relay, and you can interface it to your computer to optimize the AC on time. Double extra credit for adding a big capacitor to tune it for maximum oomph. Mine will put big dents in 3/4" plywood.
It's pretty easy to make a spotwelder. I used Kurt Bjorn's design, with my own construction techniques (ie scrap lumber) and the same transistor-and-relay interface that I use for the coilgun, so I can time the welds. It welds stainless steel like butter. I wrote visual basic and C programs that have lookup tables so I can tell it that I'm welding 14ga stainless wire and it'll know the right on-time to get a good weld. (Eventually this will be part of a LEGO-based welded chainmail making machine.)

But I think the coolest thing I had a hand in was a laser system at a now bankrupt place. We were drilling thousands of tiny holes at once, by firing a large beam (10cm x 10cm) through a multi-lens element. The beam had to be perfectly perpendicular to the lens. We had an alignment tool that consisted of a 1024-element CCD and a laser diode, that we'd shine off the lens and see where it bounced against the CCD, so we had a precision of 1/2048. (Error is doubled because of the reflection.) It wasn't sufficient -- and we'd paid $4000 for the device. Well, the laser went through 7 mirrors before it got to the lens element, and the top of the lens element was flat... so I put a front-surface mirror on it, to reflect the beam directly back the way it came, and put an index card over the laser output, with a hole punched in it. So the laser goes through all the mirrors, hits the reflecting mirror on the objective lens, bounces *back* through all the turning mirrors, doubling its error with each bounce, and you see a nice spot on the index card where the reflected beam is. You visually align the spot with the hole in the index card, and you then have your lens perpendicular to the beam to an accuracy of the diameter of the hole divided by (the beam path length * 2^7). More accuracy than we needed, for a cost of a front-surface mirror (which we already had), a paper punch, and a recurring cost of index cards (because they burst into flame after about 20 seconds.)

Right now I'm working on making a solar concentrator that'll boil water and drive a steam engine, since I have no shortage of sunlight and at high altitude water boils quickly. It's way cheaper than solar cells and it'll go "fphoof! fphoof! fphoof!" as it runs. It'll be awesome.

I build a lot of stuff.
It's easy to make a coilgun. You take a cardboard tube, like wrapping paper comes on, fill it with 1/8" welding rod of various lengths so it's solidly packed at the bottom and only maybe 1/3 get all the way to the top. You wrap an *enormous* bundle of transformer wire around the base, where the rods are solidly packed -- like 400 turns of 18 ga wire. You point it upwards, and put a ring (best if aluminum, okay if copper, so-so if steel) around the tube and slide it down to the bottom. Then briefly plug the coil into the wall. The ring will shoot off the end like a gun. For extra credit, use a 2N2222 transistor driving the coil of a big relay, and you can interface it to your computer to optimize the AC on time. Double extra credit for adding a big capacitor to tune it for maximum oomph. Mine will put big dents in 3/4" plywood.
It's pretty easy to make a spotwelder. I used Kurt Bjorn's design, with my own construction techniques (ie scrap lumber) and the same transistor-and-relay interface that I use for the coilgun, so I can time the welds. It welds stainless steel like butter. I wrote visual basic and C programs that have lookup tables so I can tell it that I'm welding 14ga stainless wire and it'll know the right on-time to get a good weld. (Eventually this will be part of a LEGO-based welded chainmail making machine.)

But I think the coolest thing I had a hand in was a laser system at a now bankrupt place. We were drilling thousands of tiny holes at once, by firing a large beam (10cm x 10cm) through a multi-lens element. The beam had to be perfectly perpendicular to the lens. We had an alignment tool that consisted of a 1024-element CCD and a laser diode, that we'd shine off the lens and see where it bounced against the CCD, so we had a precision of 1/2048. (Error is doubled because of the reflection.) It wasn't sufficient -- and we'd paid $4000 for the device. Well, the laser went through 7 mirrors before it got to the lens element, and the top of the lens element was flat... so I put a front-surface mirror on it, to reflect the beam directly back the way it came, and put an index card over the laser output, with a hole punched in it. So the laser goes through all the mirrors, hits the reflecting mirror on the objective lens, bounces *back* through all the turning mirrors, doubling its error with each bounce, and you see a nice spot on the index card where the reflected beam is. You visually align the spot with the hole in the index card, and you then have your lens perpendicular to the beam to an accuracy of the diameter of the hole divided by (the beam path length * 2^7). More accuracy than we needed, for a cost of a front-surface mirror (which we already had), a paper punch, and a recurring cost of index cards (because they burst into flame after about 20 seconds.)

Right now I'm working on making a solar concentrator that'll boil water and drive a steam engine, since I have no shortage of sunlight and at high altitude water boils quickly. It's way cheaper than solar cells and it'll go "fphoof! fphoof! fphoof!" as it runs. It'll be awesome.

3Gb/s is wrong
3Gb/s = 3 Gigabits per second = 384 MB/s = 384 MegaBytes per second
The spec is:
300 MB/s = 300 MegaBytes per second = 2.344 Gb/s = 2.344 Gigabits per second
Spec: http://www.sata-io.org/esata.asp
Calculator

This is where we started from.

Why did we change?

We made a dire mistake- three actually. During the chaos of the Civil War, Virgina's state house was burned to the ground. This gave the parasites the opening they needed. They started by getting the original 13t Amendment nullified due to an accident of history (the ratification from Virgina was never actually delivered to Washington DC, and records of it didn't exist outside of the Virginia State House). This allowed lawyers to become judges- something that had not previously happened (in fact rightly, by the original 13th Amendment, Abraham Lincoln was not eligible to serve as President- for as a lawyer he had taken the title Esquire, a title of nobility, and had therefore given up his citizenship). The industrialists from Wall Street also took the opportunity to hijack the abolisionist movement- replacing slavery with wage slavery, in which the slave owner has no actual requirement to provide a living for his slaves/employees. But the real blow to the right to rule ourselves came about 25 years later- in 1889, with the ratification of the 14th Amendment and soon after Southern Pacific Railroad's claim to personhood for corporations. With that- money, corporate money in particular, became the loudest free speech in the country, and we've been going downhill ever since.

http://users.frii.com/gosplow/13th.html This one?

Time to go buy a gun...
A 12 gauge slug in a 3" shell will penetrate most bulletproof vests at short range. Even if it doesn't, the 2500+ foot pounds of kinetic energy will break bones, put down your target and keep it down for a while (a .357 mag has about 500).
If that doesn't work, get a 10 gauge.

I reccomend the "Christian's Guide to Small Arms" for mre information.

Another good link about Phoebe. It should be noted that the satellite is transmitting blurry images of the moon sitting on a couch and drinking coffee while uttering words of wisdom which, at first glance, seem stupid. It also seems eerily older than the rest of the moons.

.... to develop educational software that could take a person from basic math (k-8 level) through algebra and on to calculus and beyond.

Most kids don't learn well from chalk-and-talk lectures that seem to begin at ever younger ages in our teach-to-the-test school system.

My ideal math system would be for anyone who needs a little bit more structure than simply reading a book by themselves can provide, whether they want to pursue a single topic or a general march through maths.

What I'm thinking of is a program that would do everything from assessing the starting level to suggesting further areas to explore in various applied topics. You would have to be very careful not to incorporate any kind of prorietary testing or content, but there are tons of older and classic math texts to mine that are already in the public domain.

This would solve some of the problems with math instruction by non-mathematicians. Think about kids in space. How did they learn math in children's science fiction of the early space age? Some kind of software that customized instruction for each learner.

What I envision is something like the best of Stanford's EPGY math courseware without the Math Races (or you could opt in for math drill if you like). One of the beauties of the EPGY math program is that it is multi-threaded. You can move ahead in areas that are strengths and catch up on other things that need more work.

I've been looking at commercial packages, especially those designed for homeschooling and I'm not finding anything as user friendly as what I have in mind. It would also provide multiple starting points and paths through the material. Say a kid (or adult) gets interested in trajectories as a result of hearing about potato launchers, or from reading Backyard Ballistics or another Ballistics website. A math newbie of whatever age would have to get through at least early algebra. Some people could start right in and play with simulations or be directed to local groups with launch-related activities. (Hmmm...hopefully not groups on some homeland security watch list...) Links in the system would bring them back to the goal topic of interest from time to time to see their progress, or would send them on to other areas.

Another feature of this program would be to incorporate the potential for multiple styles of learning. Also, once a concept was grasped, mindless repetition would not be needed in the form of worksheets and drill. Instead, you could move right along to the application of the concept.

Certain paths could follow the content outline for things like AP calculus, providing equivalent instruction to a good AP math course in a traditional classroom. Those craving external assessment (or trying to save money on college tuition) could then take a test and prove to the world that they had conquered AP Calculus.

I'm thinking that Python might be a useful starting place...any ideas?

My other idea is to have a city-wide or national or global math problem of the day, with the radio anchors yukking it up about possible solutions the same way they talk about the weekend's new movies. Problems could be on different levels, something to intrigue a different group each day.

I have built a similar device which can be found here
I didn't realize it was so dangerous. We use to put up to 120 PSI of pressure inside.
It was great though. We could launch potatoes at insane distances. We were no even able to measure the distance because the potato was going too fast and too far to track with the eye. Even when launching completely vertically we would lose sight immediately. Once, I think I heard a sonic boom while the potato was ejected.

As you would have guessed if you heard me speak in 2000, I'm not the biggest XML user. I've mellowed since then, but I still don't do a lot of XML hacking. (One of the spare-time hacking things I've while here at O'Reilly, though, is to get our internal database of "what books are at what stage" into XML for easy grepping and reuse).

Of all my work in the 2nd edition of the Cookbook, the XML chapter is the one I'm proudest of. I'm really glad you like it. Thanks!

--Nat

Why go with real guns when you can use this

More bludgeoning with this.

Thus, only downloading 0day releases within a few days of their release is only when BitTorrent works well.

True (from my limited experience), but it still is p2p, even if it is specialized.

Also, you can't search on BitTorrent. You have to find websites to download from. If the website gets shut down, so does the ability to get the files.

Yes, but again, BT is a specialized p2p tool, not flawed. It cannot (and probably never wanted to) replace protocols like those used with Freenet or Gnutella.

The design goal was to make big files available to a relatively large number of people who know exactly what they want, with everyone participating in sharing the load.

But you made me think about a definition of p2p. I would probably come up with something very general.

A slide I found suggests that there is no consensus on the term. searchNetworking has a more precise definition. Hm, I'll do some reading...

Not only did some of my friends make this in high school, I believe they won an award at our small town science fair.

I'm suprised noone has mentioned (at least in my quick scan I didn't see the link) the Pneumatic Spud Gun

According to the web page they are 5 times as powerful.

Especially not with one of these.

I think the current political climate in Germany is not in favor of new nuclear power plants, and more or less the same goes for Sweden.

I can't cite the source of where I read that at, so I could easily be wrong. But I still disagree with the policy myself...

To me it makes sense to avoid nuclear power, given that the resulting waste products are unquestionably very dangerous, and have to be safely stored for an extremely long time.

I know this is way off topic... but a nuclear power plant generates about 1.5 tons of waste (about a cubic meter) per *year* per reactor. In reality, this isn't that much, and the environmental impact isn't nearly as bad as, say, burning tons of coal every day.

Disposal wouldn't be a big problem; the real concern is keeping the waste out of reach of those who might use it to make nuclear weapons (since it has a high Plutonium content). A secure storage facility could easily be built that would handle all nuclear power plant waste for many years, I would imagine.

In reality the pollution caused by coal-burning plants is far worse. It's a known fact that if you were to use the uranium that occurrs naturally in coal (as impurities) in a nuclear reactor, you'd get some thousand times the heat generation than you would by primitively burning the coal itself...

A good paper on the subject is available here. I recently read a much better one but I can't seem to find it... the above is something I dug up on a quick Google search, but it states many of the same things.

>>Hey you know what? I am a Jewish Hispanic

So is this guy.

No offense. It's just a joke.

My parents bought me one of those Radio Shack project kits that already had all the components with little springs attached to them. You'd simply hook up wires between things and let the magic smoke out. I'm sure if I had the paitence back in the day, I'd probably have actually made the AM radio transmitter and blinkenlights things like the manual said.

It's a good thing I didn't have the Internet back then, a potato cannon or a tesla coil would have been a lot more dangerous than just a little bit of Radio Shack brand magic smoke.

Here another picture of her with a less innocnet look (titled: Heidi Wall, one of William's babysitters). I'd give her at least 18.

Pic 2

but she looks even better in person

Hey, they must be decent if Nathan Torkington uses them.

Hey, they must be decent if Nathan Torkington uses them.

This page is a good one... it also has 2 very good links at the bottom of it. I think the most interesting part of music theory is that the human ear seems to prefer tones of simple ratios.

Heidi Wall

who cares about damian conway, check out Heidi Wall

Holy shit. Has everyone seen this picture of Heidi Wall

The BEST thing that will be missed is making polarioid transfers with the old style multi-part film that is used for the hasselblad backs. I hope to god that if they stop making the film that someone else will make the same self-developing film packages, so I can take a picture, open the film prematurely and slap it down on a piece of wood or paper and get that fantastic edgy eroded look with pastel greens and browns.

For examples, go here: http://www.soulshapes.com/ and click on images on the left navbar. (framed page)

For info and howto stuff about polaroid transfers, try http://www.frii.com/~uliasz/photoart/polaroid/

:)

Mike

There is also an MP3 of the talk available from Nat Torkington, Perl 6 project leader and organizer of the Open Source Conference.

I would have to rate OLGA as one of those sites I'd love to see never go away. Luckily it is mirrored a lot and the mirrors put up whatever they want. Still if OLGA was out of its legal troubles I bet there'd be 10x as much tab submitted. I'm actually suprised in all my time on Slashdot this is the first time OLGA came up, I think it is as bad if not worse than the Napster/DeCSS/etc... cases.

This does bring up the related note of sites that just go down permanently which had good info on them. Does anyone remeber the Antics and Mayhem site with info on Fresnel lenses, Frozen CO2 and links to all sorts of crazy stuff? It moved a few times but now its gone. Guess I will just have to stick with Backyard Ballistics

- NeHe productions has over 20 OpenGL tutorials online, starting at the absolute beginning.
- The OpenGL Challenge is a weekly OpenGL compo that requires entries to be opensource. Has some *really* cool stuff.
- Romka Graphics has loads of misc OpenGL stuff, worth checking out.
- The OpenGL FAQ and troubleshooting guide is another overload in OpenGL-related material.

And besides that, I also run my own daily news site located at www.demoscene.org and is all about multimedia development, so a couple of OpenGL-related links turn up every week. Hope this helps...

---

here are some sites that I have found helpfull:
XFree86 Font Deuglification Mini HOW-TO
The Redhat White Paper explaining the font system in rh6.0

...thats all I can remember right now, the redhat page gives good instructions on getting ttf fonts setup under rh6.0
good luck

The XFree86 Font Deuglification Mini HOW-TO is a must read for anyone using XFree. Get it set up today and say good by to ugly fonts in X!

Heres a nice little howto

and it's not even multithreaded!

In netscape's defense, it's much easier to write a multi-threaded application for one platform (Windows) than it is to write one that's portable over many Unix/Linux platforms. Multithreading is not at all standardized enough to make this an easy task. They'd probably have to support fewer platforms if they were to implement MT.

Looks readable at 1280x1024 on Windows, but I can *barely* make out the font at 1152x864 on Linux even with 100 dpi and truetype fonts

That is X's fault, not Netscape by any means. Try the XFree86 Font Deuglification HOWTO

I hate it when you blind-as-bats faithful-as-christians windows-hating linux bigots ASSume that everything on Linux is better.

You must be thinking of someone I don't assume anything of the sort. I've used them both and I prefer Linux.

One more thing. Stop your pathetic whining, it's childish. If you don't like something, don't use it. Sounds like Linux would be better off without you.

http://www.ferrycam.com/livepush.html worked fine when I loaded it up with Communicator 4.6. As far as the tiny, ugly fonts go, yes that is a problem, but a fixable problem. Check out the Font Deuglification Mini HOW-TO at http://www.frii.com/~meldroc/F ont-Deuglification.html - it'll show you how to set up TrueType support and increase the size of those tiny fonts.