The primer on a 20ga shotgun shell, balanced in the crook of a tree at 100 yards. See who could make the shell fire with a single .22 long rifle shot.
Disclaimer: I am stupid -- don't try this. Know where the shell is pointing, safe backstop, etc., etc., don't try this at home. Not for human consumption. Induce vomiting if swallowed, blah blah blah... :grin: