As you might have seen, Quake 3 is one of the games which actually takes advantage of multiprocessors... allowing it to run significantly faster on the dual Macs. Here's some more interesting info: In a MacWorld UK interview with Omnigroup founder Wil Shipley: Citizen Kabuto the game recently ported to OS X by the Omni Group: "It was originally written in Direct3D, a Windows environment. We not only got the game working in a month, but also got it running faster on a year-old Mac than it runs on the fastest PC we could buy today. "We did this by taking their code and rewriting parts of it so it's actually multi-threaded now, so that on a multi-processor machine it'll use both processors. This is the first time, to our knowledge, that any game-porting company has taken an existing game and made it use symmetric multiprocessing when it wasn't originally designed to do so." He also makes comments about the speed and ease of use of Cocoa.