Hot Dang finally bought one from Ebay. I can't wait to go home and try it out. The interesting part right now is thinking about which cat will enjoy it the most. My guess is Billie, she's the spitfire.
Be careful with it until you get used to it. Most cats just go nuts and fly after the thing without watching where they're going, thus slamming face-first into walls and furniture. Start by using it in the largest space you can.