Try riding a trials bike sometime. They are really different to get used to. They look fun, but unless you ride one a lot, you can't just jump on one and go. It is damn hard to get used to standing up all the time. Your instinct tells you to sit down, but they are really really hard to ride while sitting down on the nonexistent seat.
I always wanted one until I rode one. Now I am not sure. it would take a long time and a lot of riding to get to a point where you could really have fun showing off on one.