The Study Ball gadget is a prison-style ball and chain that you can program to keep track of how much time you spend studying. Once you’ve selected the desired duration, you chain the ball to your ankle and the manacle won’t come off until the schedule study time is up.
A red LED indicator displays the “Study Time Left“ and keeps you informed as to how much longer you’ve got to keep studying. The ball and chain are made of highly durable steel and weighs a total of 9.5 kg / 20.95 pounds, which makes it difficult to move while wearing it.

For safety, the Study Ball cannot be programmed for more than 4 hours. Minors should not use it unless supervised by an adult. It comes with a safety key for emergency deactivation. Link – via coolest-gadgets

From the Upcoming ueue, submitted by mrsmojorisin.