Heard of Boot Camp yet? My favorite Machead just informed me about Boot Camp and caught me up with the rumor mill with what Apple is going to do with their next OS release (10.5).
Boot Camp (currently in beta) allows you to run Windows XP on a Mac. Upon boot up you select XP or Mac for the OS. A reboot lets you switch again. Dude, that is just friggin' cool.
Boot Camp Public Beta
Rumor mill has it that with the next Mac OS release, slated for this fall, you will be able to run Windows applications on a Mac just like any other app. No reboot, no windowing schema, just another app. Someone over there is using their noggin.
UPDATE 4/6/06:
Here are some links with more info:
Leopard to include VMWare-like virtualisation software?
Will Apple Adopt Windows?