A coin becomes invisible. When pushed into one ear it reappears in the other, visible again

Hold any small coin on the right fingertips. Bend your left arm, putting the hand near the left ear. Place the coin on the left elbow, cover it with the right fingers, and rub it with a circular motion.

"Did you know that if you rub a coin against your elbow like this, it becomes smaller and smaller?' As you say this, lift your fingers slightly and allow the coin to drop to the floor as though accidentally.

"It'll never work if I do that." Bend down and pick up the coin with the fingers of the left hand. Pretend to transfer the coin from the left to the right hand, but actually retain it in the left fingers. You simply place the left fingers on the right palm, close the right hand, and return immediately to your original position, left hand near the ear, right hand on the elbow. Don't feel guilty about this action and don't do it too fast; that will only create suspicion. Just do it naturally.

Continue rubbing the right fingers against the elbow. Meanwhile, the left fingers secretly push the coin into your left ear. "This rubbing gradually wears the coin away until it becomes very thin."

Pretend to take the now invisible coin from the elbow and place it on the left palm. "This is probably the thinnest coin you ever saw!" Both hands at this point are seen to be empty.

Pick up the phantom coin. "With a really thin coin like this I can do a remarkable thing. If I push it into my right ear like this, it passes right through my head -- there isn't anything much there to stop it -- and comes out of my left ear."

Reach into your left ear and bring out the coin which has become visible again.

A variation: Instead of leaving the coin in your ear, push it into your collar, thus accomplishing a complete vanish. Finish by showing that the coin has been rubbed into invisibility and then give it to someone as a souvenir. "Don't try to spend it for candy. They'll give you invisible candy, and that -- you can't even taste."