If you didn’t get to see Rich’s cloud chamber at the NY Maker Faire, you’ll definitely want to check it out. This thing is awesome! (And he has kits and test sources for sale!)
Here’s a video that shows it in operation. I can personally attest that it looks just as good (if not better) in person.
If you can’t afford one of his (very nicely put together) cloud chamber kits, Rich also wrote an instructable that will show you how to make your own cloud chamber with an ATX power supply and two Peltier coolers.
Thanks for the review, Rich!