Xv6

Xv6, if you haven’t heard about it, is a reimplementation of Version 6 Unix in ANSI C for x86 processors for an operating systems class at MIT. When I first came across it a while back I wanted to play with it, but unfortunately it’s rather harder to get working under OS X because xv6 uses ELF for its executables while OS X uses COFF Mach-O (update: I’m not sure how I horked that one up.