Update: The below was tested on Parallels Desktop 6. Commenters have reported that it doesn't work on Parallels Desktop 7, which is indeed a drag. When I have some time I'll take a closer look. Yesterday, I explained how to install Snow Leopard as a guest in Parallels (or presumably another ...
Snow Leopard as a Parallels/VMWare/VirtualBox guest OS
Update: The below was tested on Parallels Desktop 6. Commenters have reported that it doesn't work on Parallels Desktop 7. I'll be taking a closer look at some point. One bit of under-the-radar good news in Lion is that Apple has changed the licensing terms of their End User License Agreement: they ...