I have over the past few day built a master/slave arm set. the master is 4 100k potentometers mounted on a frame to fit my arm, and wired into a joystick port. 2 pots in the shoulder give elevation, and rotation. 1 pot for the elbow. and one for the gripper. 4 sevos make up the arm, 1 coresponding directly to each potentometer, and making an arm that is roughly the same dimensions as my arm, and has nearly the same degree of freedom, though it is somewhat weak.
the interface is an ifi robotics issac16 setup, the operator interface takes joysticks as input, and gives a wireless link to the robot controller. the robot controller is a basic stamp 2 or something, and has 8 PWM outputs.
I am planning to use it to hand out candy for halloween.