I have heard that such devices already exist. They are a NTC cap that goes over the end of the bulb. http://donklipstein.com/bulb1.html#ss http://donklipstein.

I have heard that such devices already exist. They are a NTC cap that goes over the end of the bulb. http://donklipstein.com/bulb1.html#ss http://donklipstein.com/bulb1.html#ss