Traffic light hack keeps tabs on your system

In an attempt to communicate more clearly to people when he is "busy" on his computer, one DIY'er in Japan has created the TrafficStop, an LED traffic light that interfaces with some custom Mac software and displays information in the familiar and easy-to-read three light system, updating the lights according to a user-defined threshold. With a hack like TrafficStop, your "work" will never again be "interrupted" by "people".