I play games in my off time - which I haven't done in about 4 weeks. (Right after I got it I put in an old hard drive, booted up, and played Homeworld 2 for a few hours. (Ran great!
Much Much smoother than on my dual Athlon MP 1800 machine. (Which has since bit the dust HARD).
Aside from that, I run FormZ - architectural modeling software, 3D Studio Viz, AutoCAD, Macromedia Flash, Photoshop CS, Maya, Rhino, Lightwave, and anything else that has free trial offers. (Sketchup is my newest toy - not liking it thus far, and no - it isn't a condiment modeling software. It is for architecture too.)
I also play Praetorians, Sim City 2000 and 3000(of course), Worms Armageddon, etc...
My next upgrade is going to be an Nvidia Graphics card (either a workstation or a 6800 - not sure yet what I can afford.) That's about it though. If you have any more questions, feel free to ask - but try to answer some of mine too!!! (just kidding around.)
Iwill Zmax DP SFF Barebones kit... (300W PSU, 8 USB, 1 FW, etc...)
Dual AMD Opteron 275's | 2 Gigs (2 Dimms 1024Mb) Patriot RAM 3-3-3-8
WD Caviar 80 Gig HDD - System
WD Raptor 74 Gig HDD
ATI Radeon 9800 Pro 256
NEC ND-3520A Dual Layer DVD±RW | Mitsumi Floppy/Card Reader combo