Well, lets see...ProDos, ProDos16, OS4/OS5 (AppleIIgs), OS6/7/8/9.X (Macintosh). When I got a copy of OS X 10.0 free from Apple for myPowerMac G4 D/A my first impression was WOW! To this date, I am still impressed with OS X. On the Hackintosh side, obviously I started with good 'ol Tiger...on AMD 64 3200+ and a P4. However I had Mac OS running via VirtualPC for Windows 95 long before that, which was a joke. I also had bootable Windows 95 on my G4 via VirtualPC with NO Finder loading at all. Long live the Hack!!!!