It warms my heart to see so many OS X and linux nerds on the board.
My main machine (iBook) is an OS X machine, but my desktop is a gentoo machine. I also have a swappable hard drive on my desktop for XP, but I rarely use it. There are a couple of software packages I use every now and then that require winblows. I hate MS.
I'm a linux sys admin for a research group so I support several gentoo, redhat, and OS X machines. No winblows!!!