So far i've got Firefox, VS C++ 2005 Express, the August 2006 DirectX SDK (which i'm really impressed with), Paint.net, SharpReader (RSS reader), Microsoft's virtual desktop powertoy (the one thing I really missed in OS X), Open Office, Python, X-Chat 2, Blender, and VMware Player. What am I missing that you can't live without?
VMware is pretty amazing. This entry from Rob Loach inspired me to try it out. I had been thinking about dual booting, but so far VMware's performance is up to my needs. Something about being able to run Windows and Linux side by side makes me feel all warm and fuzzy inside. Here's a screenie: