SoftGrid available on MSDN
This is probably old news, but is new to me. I logged into MSDN to check something else out and saw that SoftGrid is now available on MSDN. I have had the bits internally for some time, but now anyone with MSDN login can get it. 
If you have never heard or seen SoftGrid you would be quite amazed how powerful it is. Unlike most virtualization software which virtualizes OS's (VMware, Virtual PC, etc.) SoftGrid virtualizes applications - so you have have multiple versions of the same application installed and running at the same time without conflicting with each other! Now I have not had a chance to play with this to see how it handles various dev related software like the debugger, various windows services, IIS, SQL Server, etc. but it sure works like a charm for "client app's". If you want to see more then check out Getting Started with SoftGrid and the Lazy Admin's What is SoftGrid.
