That's the aim of Codeweavers' CrossOver Games software. It's a special version of the developer's CrossOver Windows emulator for Mac and Linux designed with gaming in mind. It launches today, at the low, low price of $US 39.95.
Emulation of basic hardware and operating system calls has come a long way in recent years, but graphics has always proved troublesome. While I don't have experience with the latest iteration of virtualisation and emulation packages, I do know that previous attempts to support gaming have been flaky as all hell.The press release accompanying the launch states that CrossOver Games will be more "bleeding edge" than the company's other products. I'm guessing this means it'll see improvements and updates sooner, even if they're rough around the edges.
According to Codeweavers' site, CrossOver Games supports Half-Life, World of Warcraft (which runs on Mac natively anyway), Civilization IV, Call of Duty 2 and a load more ancient titles.
To be fair, emulation is a tricky beast, so you can't pay the developer out for trying. At $US 40, it's a hell of a lot cheaper than a PC with a copy of Windows. Keep in mind that if you want to play the latest PC games on a non-Windows system, this isn't the answer.
CODEWEAVERS RELEASES CROSSOVER GAMES FOR MAC AND LINUX [Codeweavers]