Somewhat related but if you just want to play around and you have Parallels, you can install that by going to new virtual machine, and the developer preview version of win 8 is one of the choices. It expires in two weeks.

It works, but I couldn't find a way to install Boot Camp stuff, so it's pretty miserable experience (no right click, no two-finger scrolling, have to manually find Wireless drivers, I don't have audio working, etc.).

Bummer, hopefully it will be easy to set up. To get a good feel for this we really need multitouch support.

At least with the dev preview, the way to do it was to fire up Boot Camp in Lion, have it make the Windows 7 drivers USB stick, then quit Lion. Pop over to Win 8 and then install the drivers. But they don't all work (at least, I never got multitouch working).