I use Windows 7 at home for my main rig and my HTPC. Using Ubuntu Linux on my security camera server, Windows Server 2k3 on my web server, there's a couple of Windows XP boxes floating around for different things (like the media box for the arcade), my classic gaming PC runs Windows 3.1 and the machines I use for editing at school are running Mac OSX. I also have a bit of a classic computer collection that runs a variety of things (Commodore 64, IBM PCjr, Atari 800xl, TI 99/4a, Amiga 500, Apple IIgs, Sun SPARCclassic, Atari ST).