I recently downloaded and installed MorphOS the Amiga Compatible operating system for PowerPC G4 systems. So far its really cool, Especially if you are into Amiga, You can run most classic amiga software on it natively :), If you got a spare iBook G4 or old G4/G5 based system laying around, Give it a look. Its a ton of fun to work with :) http://www.morphos-team.net/