Chops

This looks a very impressive trick (especially with glow in the dark balls).

Step 1 : Juggle normally

Step 2 : Swipe your first hand with ball down across your juggling pattern and throw it so it goes on the outside of your other arm.

Step 3 : Swipe your other hand down across your pattern and throw on the outside of your other arm.

Step 4 : By this time your first hand should have already moved back to its original starting position.

This trick is amazingly fast at first.