Here is how to make a DIY iPod cradle which fits into a car cupholder, similar in concept to the ones sold by companies such as Belkin and Griffin. Of course you could adapt this design to other devices: handheld GPS, phones, other MP3 players, palmtops etc.
http://www.hartnup.net/misc/iPod_cupholder/
While often used in electronic music, you can oftentimes use a ribbon controller wherever you'd use a potentiometer, with the caveat that you have to keep pressing down. I've used this design to control display brightnesses and motor speeds, as well as hooking it up to an ADC & microcontroller to send MIDI CC info.
http://asmidius.googlepages.com/
Basically the AccelR8 is a device for measuring acceleration. It can measure +/- 2 g. As it contains a microprocessor, it an also measure time. This opens up some interesting possibilities. If we have the acceleration and the time, we can find speed (V), as V = a * t.
http://www.myplace.nu/avr/accelr8/index.htm
This project describes an innovative multimedia thermometer of great visual impact. The temperature is shown on an ordinary TV with crisp, full color graphics. To add more magic, pictures can be animated, and stereo CD-quality audio announcements can accompany every temperature change. Pictures can be varied according to the application.
http://www.riccibitti.com/dvd_therm/dvd_therm_article.htm
This article describes how can you use a Famicom to NES converter board and an empty NES cartridge case to build a permanently-converted Famicom game for play on a regular American NES.
http://www.vintagecomputing.com/index.php/archives/39
I needed a super long VGA cable to reach from the LCD my computer, which were on opposite sides of the room. Initially I was going to move my computer to the projector but decided against it. I read a few articles involved with VGA conversion and decided to give it a shot.
http://www.elephantstaircase.com/wiki/index.php?title=VGAtoRJ45conversion
Oww is a software project, to communicate with the Dallas 1-wire weather station and other 1-wire sensors, presenting live weather readings, logging data to file, uploading data to weather Web sites, and sending data to other programs through a command line interface.
http://oww.sourceforge.net/
We decided to build a fully functional dialup router using a spare 56k modem from our old dialup bank, a dialup account with a national provider, and a Netgear wireless firewall. The basic philosophy by this device is that it acts not just as a dialup router, but as a DHCP server for your local network on the same subnet your network would ordinarily be using in full operation.
http://www.makezine.com/blog/archive/2006/01/how_to_building_an_out_of_band.html
For a while I have wanted to control things with a serial port. It was pretty easy to control a relay with a serial port. With a standard serial port you can control 2 relays. (with a parallel port you can control 8 relays, but I don't have a parallel port on my system).
http://www.windmeadow.com/node/4
With a low-cost general purpose microcontroller like the PIC16F628, bits and pieces of cheap, commonly available electronics components, and LOTS of code, you can build many interesting `toys' and hook them up to your Linux machine - a really great learning experience for the hardware hacker who wants to learn Linux, or the Linux hacker who wants to learn a bit of hardware. This article describes how I went about building my temperature-sensing project - amateur Linux/hardware hackers might find some of the ideas useful when they start building things on their own.
http://linuxgazette.net/issue99/pramode.html