This is a classic trick that has been around for a million years, but still gets the same response even today as it always did.
You show a vase with a lid. You lift the lid to reveal a ball. You then proceed to take the ball and keep it back in the pocket and close the lid. When you re-open the lid the ball reappears in the vase. When the lid is closed again, the ball appears back in the pocket and the vase can be shown empty.
A lot of other easy to do routines are possible with this classic Ball & Vase.
The vase stands at around 4" tall.