A very easy trick to perform with an amazing effect!
Place a small ball in a clear box. Put the lid on the box, cover it briefly with a handkerchief, and when the handkerchief is removed- the ball has vanished!
Another effect: Leave the box empty. Place rubber bands around the box. Place the ball on top of the box. Cover it with a handkerchief, and when the handkerchief is removed- the ball is now inside the box!
The audience can be given the box to examine.