Panther on Debian/m68k.

Some crazy fellow tried to run Mac OS X Panther (that's 10.3 if I'm not mistaken) on a Centris 650 (a 25Mhz m68k). Procedure: run PearPC on an athlon or another insanely fast box to install OS X in an image that PearPC can boot from. Then copy the image to the Centris, run PearPC on that box, and, uh... wait a week for the stuff to boot.