A through preflight. No pilot would fly without one. In this event, we take that concept one step further. An aircraft, usually some kind of light single, like a Piper Archer, or a Cessna 182, is 'bugged' with discrepancies. Small things are wrong with it, and you not only have to find what's wrong, but you're timed, limited to 12 minutes.
Sound like fun? If you think that spending an hour or two a week at the airport crawling around airplanes is fun, you're right. We practice on our own aircraft and have internal competitions to determine which two go to competition.
We do have tryouts, since time and practice aircraft are limited (we really can't go around breaking airplanes, people tend to get upset!) The only restriction is you can't have an A&P certificate, and if you don't know what that means, don't worry, it means you're eligible.