You ask to borrow a 10p coin. You show both hands empty. The coin is placed on the back of the hand. After a few seconds the coin stands up on its edge. The hand is now removed and the 10 pence remains suspended in mid-air. Slowly the coin moves up and down, then it actually travels several feet away from you. The coin stops for a second or two and then comes back to you. The spectators face is a treat.
After they have recovered and got up from the floor you hand them their coin back.