Animatronic C-3PO replica
This animated C-3PO replica, made by one of our customers, moves its eyes, arms, head, and—in true C-3PO fashion—tells tasteless jokes. The movements are animated by a Pololu Mini Maestro 18-channel USB servo controller. A Pololu RC switch with relay (controlled by the Maestro, not an RC transmitter) shuts off the power to the head to avoid servo humming noises. (You can achieve a similar result with most servos by not sending RC servo pulses, which a Maestro does when the servo target is zero.)
The customer’s C-3PO web page has more videos and extensive documentation on how the replica was built.