I'm looking to expand my 120GB HD. I've just started using Parallels with Windows 7, and since it worked phenominally, I would like to use Bootcamp and load a couple more OS's. I figured I need some more space. I've been reccomended by a couple people to look for a Seagate 7200rpm drive. I've found a 320GB and a 500GB. I'm looking to load Vista, XP, Windows 7, Leopard (obviously) and maybe one more. Since I've never used Bootcamp, how much space should I allocate for each OS? Leopard will be my main OS and the Windows OSes will only have programs. As of right now, I'd say I use approx. 75-90GB of space on Leopard, after deleting approx. 30GB of stuff. Thanks!