We used to spend a lot of time making projectiles.
Its amazing what weapons you can make out of standard office equipment: blow guns with drafting mylar that shoot push pins hard enough to stick in walls (or people's butts) at 10 feet, pencil missile launchers with engineers scales and rubber bands, etc. (Plus when I was in the mines or doing geophysics, I got to use dynamite, drive loaders and trucks, and generally have fun).
(MichaelS wasn't picked again, Tue 26 May 2009, 20:11, Reply)