I've heard this idea bandied about, but wasn't sure if anything ever came of it. This may be too socially irresponsible, but I believe the concept was: we all chip in to rent a bog standard rental car. Then we take turns driving it around an autox course to see who can get the best time.
I suspect most rental contracts have fine print that excludes this sort of behavior ::Banned:: , but it sure would be fun! ::Drive1::