I have Panther installed on my iMac G3 333 MHz. It's slow, and I don't turn it on much. I also have a Power Mac G4 (Quicksilver) running Leopard. It's slow, and I don't turn it on much. ;-) Both systems can run most Apple and third-party PowerPC software. The G4 isn't fast enough to play Flash video at more than one frame per second. I understand Apple's reservations regarding Flash on its ARM chips.
