Screw-In Motion Sensor
Don’t feel up to the awesomeness that is Motionbulb? Then check out this screw-in motion sensor.
How does it work? Simple. Unscrew your existing light bulb, screw the sensor in position, and screw the light bulb into it. It will then automatically turn the light bulb on when motion is sensed. And it will turn it off 4 minutes after motion stops.