Bought a "broken" iMac G3 400 from Savers for $20 a few weeks ago, fixed it (only needed a hard drive) threw 512 MB of RAM in, and now it's dual booting 9.2.2 and Tiger. Makes a great DVD player/silent web browser/heating device, and I can finally use all those odl magazine discs I accumulated over the years!
Here's OS 9 because it gets more usage.
EDIT: Yes I know I only post screenshots of old Macs, but you don't wnat to see my boring-ass main desktop and its thousands of icons on the desktop do you? Just imagine the exact polar opposite of these empty Linux screenshots where all you see is the wallpaper and a FluxBox taskbar and you're close.