Build a 10-12 foot high half-pipe in the middle of the ice rink. Everything is normal about the ramp with the exception that the flat area is not wood, it's ice. So, essentially it is two quarter-pipes facing each other to make one full half-pipe. Get a bunch of skaters and BMXers to try it out. It's a little like the gauntlet . . . perhaps have hockey players fire pucks at them while they are skating.
Want to master Microsoft Excel and take your work-from-home job prospects to the next level? Jump-start your career with our Premium A-to-Z Microsoft Excel Training Bundle from the new Gadget Hacks Shop and get lifetime access to more than 40 hours of Basic to Advanced instruction on functions, formula, tools, and more.