Yeah, you thought you were done being green. You know all of those lightbulbs you swapped out? Yeah, it may be time to trash them because there is a greener variety out there with the Motionbulb — a green lightbulb that includes a motion sensor.
The Motionbulb is a standard CFL that switches itself on and off thanks to an infrared sensor that detects movement. A switch on the lightbulb allows you to control how long the bulb will stay lit before turning off without movement. It also has an adjustable light meter so it will not turn on at all during daylight hours. Each Motionbulb is available for $20.