As mentioned on Wired, if you buy a new copy of Alice: Madness Returns for PS3 or Xbox 360, you'll get a voucher for a free download of American McGee's Alice for PC. If you buy the game used, the voucher will cost $10 (still cheaper than finding a retail copy of the original game).
I hope the sequel doesn't suck but at the same time I'm glad that this offer is out, since I wanted to replace my Mac copy of Alice with the PC version...
Source: Wired