Magic Stop Light Cards/Super Signal Traffic Light

A traffic signal jumps through the air. The magician shows a black card with the colors of a traffic light on them, Red, yellow and green. He also shows a blank card, which he sets onto a spectator's hand. Like magic, the green spot vanishes from the traffic light card and appears on the blank one the spectator is holding! Easy for anyone to do. Self-contained and nearly self-working -- an easy demo that requires no skill