Tom's Trick (unofficial name)
is a three ball pattern established by Thomas Wood. It is essentially the
Boston Shuffle with a chop inserted before each slam. The pattern gained a
bit of infamy after being touted as "mathematically impossible," though this
claim was easily debunked by Nathan Peterson in his
(note that his asymetric interpretation is slightly different than my own,
since I am referencing a more direct demonstration posted by Woods after
Peterson had solved the trick). Ironically this "mathematically impossible"
trick is actually a fairly easy three ball pattern, as long as you are
already comfortable with Chops and the Boston Shuffle.
To begin learning Tom's Trick, start with two balls in your non-dominant hand and one ball in your dominant. Raise your dominant arm up and shift your non-dominant hand to the center of your body. Perform a chop with your dominant hand while simultaneously making a fairly vertical under-the-arm throw along the dominant side of your body with your non-dominant hand. As that ball reaches its peak and begins to descend your dominant hand should be finishing its chop. Once that arm motion is finished you are going to make a throw from your dominant hand toward the non-dominant side of your body, clearing space for your dominant hand to catch the under-the-arm throw. Your non-dominant hand will then perform a slam throw to your dominant hand, claw catching the ball your dominant hand just threw.
As shown, practice this on both sides. For the next step you are going to make a throw from your dominant hand toward the non-dominant side of your body before catching the slammed ball (instead of simply catching and holding both balls as done in the previous step). As that ball crosses through the center of your body, make a normal Cascade-style throw from your non-dominant hand toward your dominant hand. After that throw you are going to raise your non-dominant hand up and grab out of the air the ball that had been thrown by your dominant hand. You will then perform a chop with your non-dominant hand while simultaneously making an under-the-arm throw with your dominant hand, clearing space for that hand to catch the Cascade throw previously made by your non-dominant hand. The under-the-arm throw will be caught by your non-dominant hand after the chop is completed.
Practice this on both sides. Notice how the final under-the-arm throw and chop are a mirror image of how you started. To continue the pattern simply repeat the step using the opposite hand configuration. Overall Tom's Trick is a relatively easy pattern to master while being surprisingly enjoyable to juggle.