The creator of the Segway has been commissioned by DARPA to create a prosthetic arm that amputee soldiers can use to eat or perform daily tasks. Of particular use to double amputees, the arm is controlled (somehow) by synapses. In other words, by your thoughts.
Personally, I think the idea of being able to replace defective or damaged body parts is awesome. Restoring sight to the blind, sound to the deaf, etc. This kind of technology goes a long way towards great things… as long as they can't start controlling our minds… that would be bad.
Be sure to check out the article and video here.