The Third Thumb Project is a truly interesting and innovative idea. Instead of using prosthetics to replace lost digits or limbs, the Third Thumb Project is exploring the idea of adding them to increase our abilities. In this case, it is adding a third thumb (second on one hand) that can squeeze things just like your natural one. It is controlled by sensors under your toes. That sounds weird at first, but when you think about all the things that use our hands and feet together, it makes some sense. Driving, climbing, sewing, etc. For the time being, this is just a prototype and not available for sale, but I could definitely see this kind of thing catching on in a much cooler version of our future.