Wow - looks like CXBX, the XBox emulator, can succesfully run its first commercial game at full speed on a Pentium 4. And if you “overclock” it, the game runs at 4x speed.

http://www.caustik.com/cxbx/index.htm

Good to know that someday I’ll be able to play Halo with the same ease that I currently play Bomberman.