Vanish a coin with no sleight of hand.
The magician borrows a quarter, and places it under a handkerchief. The spectators can feel the coin underneath the hank. The magician then holds the hank over a small glass of water and drops the coin inside. Upon removing the hank, the coin has vanished. The water is poured out of the glass and the hank is shown free of trickery.
A classic of magic.