Wired News: Advent of the Robotic Monkeys:
"If a monkey is hungry but has his arms pinned, there's not much he can do about it. Unless that monkey can control a nearby robotic arm with his brain....
If mastered, the technology could be used to help spinal cord injuries, amputees or stroke victims. ...The prosthetic limb, the size of a child's arm, has working shoulder and elbow joints and is equipped with a simple gripper to grasp and hold food. The monkey's arms are restrained at its sides and as the monkey thinks about bringing the food to his mouth, electrodes in the monkey's brain intercept the neuronal firings that are taking place in the motor cortex, a region of the brain responsible for voluntary movement."