Called a Thermocube. Cost about $15 at teh hardware store. Looks like an outlet "expander" one that makes a regular outlet hold extra plugs...except it has a thermostat built in to it. It cuts off power to anything plugged into it when the temp reaches 40 degrees- comes back on at 35. I am using it for my heat lamps- saves the constant plugging/ unplugging business Probably you have all heard of soemthing liek this before, but it was new to me so I was really excited to find it. Just what I was needing!