High school student Leon Overwheel built this sick flyer robot to hand out leaflets Rye High School science fair. It uses an ultrasonic sensor to detect a visitor, then pulls a flyer off of a pile and hands it to the visitor. My favorite details are the Fergelli linear actuators and the Mindsensors Flexi Cables. He even hacked together a NXT-Power Functions adapter cable.
Device-wise, the robot consists of the following functional parts: