I came across this article at CrunchGear on how to record analog audio on to a floppy disk. It's a pretty good hack, so check out the article: Video: Recording analog audio to a floppy disk
Below is the video that was featured in the article. It was produced by The Fat Man and Circuit Girl which looks like a great site to find some interesting hacks, some using surplus equipment.
The Fat Man and Circuit Girl are George Sanger and Jeri Ellsworth respectively. Jeri is best known for her work on the Commodore 30-in-1 Direct to TV, and she has a YouTube page at: http://www.youtube.com/user/jeriellsworth. I especially like the video: CDROM Tray Cup Warmer / Cooler with Over Clocked 8bit CPU's and Peltier Cooler
Now I know a many of you have lots of surplus stuff lying around, so The Fat Man and Circuit Girl should give you plenty of inspiration to hack away at some of it. Cheers ~ Jim