I installed the GPL Open Source virtualization app VirtualBox tonight with Windows 7 so I could run the BlackBerry simulator on my Mac. It runs basically everything you would need:
Presently, VirtualBox runs on Windows, Linux, Macintosh and OpenSolaris hosts and supports a large number of guest operating systems including but not limited to Windows (NT 4.0, 2000, XP, Server 2003, Vista, Windows 7), DOS/Windows 3.x, Linux (2.4 and 2.6), Solaris and OpenSolaris, and OpenBSD
Been running it for a bit, and so far so good, and really impressed by how easy it was to setup. Score one more for Open Source 
VirtualBox even has some well made screencasts to get you started. I’ve included one below:
Good stuff.
awesome … loved it
Great tutorial. thx 4 sharing