In summer time when the ice is off the rink, pad the boards, cover the concrete base in hundreds of thousands of ball bearings and let the kids play around with boogie boards and the like. The main event though would be the roller derby. Contestants wear full body suits which have hard plastic skid pads covering all body parts not required for movement. The object of the roller derby is ten laps around the rink but the only surfaces upon which to propel yourself after the running start will be the boards themselves or other contestants, so spin, angles, and trajectories will all need to be determined on the fly in order to maintain momentum.
I picture some contestants knocked and spinning madly out of control too far from the nearest boards to affect their course while others try to use that momentum to slingshot past. Cutting corners is essentially part of the game so there will be an inner oval dead zone which, if entered, eliminates that contestant.
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...and of course there will be a beer garden.-- 2 fries shy of a happy meal, Mar 29 2009 [+] It sounds like fun but I can see a nasty accident waiting to happen if someone has long hair or an untied shoe lace.-- Jscotty, Mar 29 2009 ahhh very close. I never imagined anyone trying to stay on their feet though. The whole thing would take place on a persons back, front or side while trying to run against or bounce off of the walls.-- 2 fries shy of a happy meal, Mar 29 2009 random, halfbakery