There are some wicked ideas, and then there are some truly wicked ideas. Swoopo is about the most wicked I've come across in a while. It takes a few minutes to understand what's going on, but when you do you can't believe it's really happening.
I'll blow your mind even more: a current auction for $225 worth of "bids" is currently at $480. These are bids you can buy on the site for $225.