I've been running the 64-bit version of Windows Vista RC1 (the Ultimate Edition, of course) on my home machine which is a retail HP a1450n (quite an amazing box for $800, if you ask me.) This was a major step forward for me, as I'm an avid World of Warcraft player and moving from my tried and true 64-bit Windows XP to Vista RC1 was a leap of faith. I'm happy to say that with ATI's 64-bit beta drivers for Windows Vista RC1 things are cooking along quite nicely ... but enough about games.
My teammate, Beth Patton, pointed me at a 64-bit version of Virtual PC 2007 to run on said machine and it screams! I went out and purchased a new Segate 7,200 RPM 100GB external "pocket" drive to host my virtual machines and I'm happy as a pig in you-know-what right now. Now I finally have a reason to purchase at least 2GB more of RAM. I'm also tempted to go buy another 64-bit machine and do some server consolidation at Casa dé Hambone.