I installed Windows 7 when they were giving it as a release candidate, and had never really expected to keep it on my MBP. But since then, I bought some games from Steam during the holiday sales and don't want to lose them. I'm also going to away to college and won't bring by desktop Dell with me so I'll probably need Windows for something. Is there any way I can buy or "register" the copy of Windows 7 I have installed right now so I don't have to redownload the stuff on Steam (or reinstall Windows for that matter)? If I do have to reinstall, should I be worried about DRM on the games (Bioshock in particular)?