Brad Addams - Halo

Hand a balloon to a friend and ask her to blow it up. The take the balloon and do the impossible. As you concentrate, the balloon moves at first. Then a little more. And then, on its own, the balloon floats right out of your hand and up toward the sky.

You can let it float back down, or snatch it right out of the air.
As a kicker, you can then cause the balloon to pop through concentration alone.