If you had a circuit hooked up to a light bulb, but controlling a the light bulb were two sensors wired into the circuit. One sensor turned the bulb on when there was no light, and the other turned it off when there was light. I'm not sure if that would be all one sensor, but garden lights work somewhat like that. Anyway, what if the sensors were mounted directly in front of the light bulb, facing it, so they worked based on its light. What would happen when you turned it on? Would it act like a strobe light or just explode, and would the effect be different with LED's? Also, would you need to put some other mechanism in to slow the sensor's signals?