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I should also point out Tangent's tutorials, which are fantastic introductions into wiring and soldering even if you're not interested in audio work.

I would start with DIY audio electronics, since it's easy to test, usually not dangerous, and you get a useful product in the end. The CMoy amplifier is popular and has several good tutorials written about building them from RadioShack parts for about $25. The best is from TangentSoft. The CMoy has a simple circuit that should be pretty obvious to anyone with some classwork in electrical engineering. You can build the amp without that knowledge, too. If you enjoy it then there's a huge range of other more advanced kits and schematics to build from.

I have used Mindstorm kits in my classroom, and they are great (and actually cheap comparatively. I was able to get a 3k grant that allowed me to purchase 15 kits from Target on sale). They do, however, require lots of prep time to develop and test an idea before bringing it to students. A nice benefit is that there is tons of existing curriculum and books to help out if you go this route, which is the only way to go for classroom robotics.

My dad, a middle school science teacher, would have his kids make Rube Goldberg machines for a GATE class. The projects were always outstanding, and it really puts the focus on ingenuity and original design. Now, it's not really DIY tech, as the point is that there is no point, but there are many practical mechanical principles, and if you really get adventurous, chemical or electrical principles (which may lead directly to important first aid principles).

An idea that I have had, but haven't done, is to have students build a simple amplifier. The reason I haven't done it is that I can't figure out how to really make it a great educational experience. I want them to use the soldering iron, I want them to learn how to use a multi-meter, and that's all covered. But I also want them to do some design or discovery, or at least understand what's going on, and a simple amp design is usually going to involve an opamp, which isn't going to make any sense. Or maybe it does and I'm just not thinking about it the right way. A project like the Cmoy pocket amp would be perfect, especially as it can work with a super cheap opamp like the tl086.

Why not a simple op-amp based headphone amp? Like this one: http://tangentsoft.net/audio/cmoy-tutorial/ You can present the simple an Op-Amp model since you only really need algebra to understand how an Op-Amp works at a high level. Plus in the end the kids will have a cool and useful device.

If you are into (or want to be) audio

http://tangentsoft.net/audio/

Else

http://www.allaboutcircuits.com/

See, for example, here. It was similar enough to bsd sockets that Microsoft could claim "compatibility", and sufficiently different that in practice you had to re-write all your code.

> The audio output (read:amplifier section) of most PDAs totally sucks ass.

The audio output (read: amplifier section) of most MP3 players totally sucks ass. Not until the shuffle and 5G iPod did Apple get it (mostly) right... and others are pretty far behind. iRiver had the right idea with digital output, but for some reason they killed that feature (oh no, we wouldn't want anyone to copy music!!! that would be HORRIBLE.)

Anyway, you can mitigate the quality problems by building youself a CMoy or similar amplifier. This site, http://tangentsoft.net/audio/ is excellent reading.

I use a slightly enhanced CMoy to drive my headphones from my Powerbook, and it makes a world of difference. Still not as good as something with a clean output, but pretty good nonetheless.

However Lame List contains a lot of wonderful nuggets.

I must disagree with the article however, there are so SO few times that disabling the Nagle algorythm is the correct answer that the standard answer when someone asks about it on the networking forums is that the asker doesn't understand Nagle, and to reenable it. Telnet is even a bastard case in that your networking performance may actually go UP sending smaller bursts of network characters, rather than one at a time, each in its own packet. But you have to measure your own performance.

Frankly none of these suggestions will get you ultimate performance from a 10 Gig networking stack, and that is where networking finally becomes fun

Actually, Overlapped I/O is specific to the NT kernel 4.0+, although Windows 95+ emulates it at the API level (except for serial and parallel port I/O, where it's actually native).

See the MSDN articles on struct OVERLAPPED and CreateFile(FILE_FLAG_OVERLAPPED) .

Improved audio output. I understand the need to provide maximum playing time, but I would appreciate a decent output circuit to make my Etymotic ER-6 headphones shine. As of now, I need something like this to drive my headphone corectly and make my tunes sound heavenly.

Yes, I can use a more effecient pair of open ear headphones, but I don't want to be one of those jerks on the express bus where
eveyone can hear that I'm listening to Led Zeppelin's "Since I've Been Loving You" at moderate to high volumes.

Sorry, but you're wrong. No ATI All-In-Wonder card supports MPEG1 or MPEG2 hardware encoding. It's all software driven (licensed from Ligos) And it's filth.

There are a few hardware MPEG2 encoder/decoder's out there that are PVR's. A few that come to mind are:

* Sigma Designs REALMagic DVR -- My personal favorite, has had the best quality so far, both at low bitrates and high.

* Hauppauge WinTV PVR -- It's decent quality for those on a budget. Encodes high-bitrate MPEG2 like a charm.

A webpage detailing and reviewing a ton of MPEG1/MPEG2 encoders (both hardware and software) can be found here.

Every 1/60th of second, the electron gun runs from left to right on the vertical axis and paints every other horizontal axis, and 1/60th of a second later it paints the other horizontal lines. There are 525 lines in NTSC, although only 480 show up on the screen as the rest are black and/or encoded. This ends up with the 30 frames per second rate. This was origionally based on the timing from the 60 Hz power in the US (since early TV's didn't have much in the way of timing electronics), and it's why PAL is 25 FPS as European power is typically 50 Hz. Of course today, with digital timing this isn't necessary, and neither is interlacing, as that was done to address a limitation of the very first generation of TV.

If you really wanted to be a geek, you'd point out that color NTSC isn't actually 30 FPS, it's 29.97 FPS. Originally NTSC was 30 FPS, but it was slowed a tad to allow for the color signal when they changed the standard to include color.

Another know-it-all wannabe trying to show off his know-it-all skills. What a suprise.