Microsoft needs to port Halo 3 to PC. It's not making you any money on the Xbox (I mean, ODST, Reach, and 4 have come out since), the PC crowd will still buy it though! Seriously!

Let me play it without having to turn in my PC Gaming Master Race membership card. (Read: buy an Xbox, use it for Halo and nothing else, which seems a tragic waste of money)

EDIT: Actually I wouldn't even use it for Halo, I'd try to play it once, fail hilariously because I can't play dual-stick FPSes worth a darn, and go back to PC