GuiltyAsCharged dares Everyone to
do the bottle cap prank.
More about do the bottle cap prank.
Watch. And since you can't fully understand them... when I do this prank, I say "The record of slaps to knock the cap off the forehead is 3. Mine is 6. Try and see if you can get under 10." http://www.youtube.com/watch?v=5dLilU_c3aA