I mentioned earlier that Nerf dart gun tag would be fun to do in the math department, after hours.
I should have expected that some people are much more nerdier than I am. A company makes a toy pistol that shoots balls of velcro. Now you don't need to look absurd wearing a Nerf target vest: just wear a sweater.
Of course, even nerdier people would just shoot little ninjas at each other. And the real nerds already have a USB missile launcher hooked up to their computer.