Why would you want a traffic light in your house? OK despite it’s look traffic light can be used simply for fun, or can display some specific information, like email or IM notification, weather alerts, or other you can think of. Rockwell Schrock have made such traffic light that can be controlled via USB directly, or can run predefined sequences.

Circuits is based on Arduino schematic that accepts commands via USB interface, or simply runs predefined sequence of light switching. Lamps are controlled via electromechanical relays so you can hear a click noise too. This is really fun evening project to make.