But you and johncolanduoni both say that it's nontrivial. However, blibble says that it's easy with current ATI consumer hardware.

I know a few gamers who would like to relegate Windows to a locked-down VM ;)

Well, it was a while that I was looking at it. Combine that with my opinions about gamers' hardware and system software knowledge (not very flattering, outside of knowing which brands and models are "best"), that's how I came to the conclusion, that it might be difficult for them.

But do not take that as discouragement, your friends definitely should try it on their own.