The other day I was checking out those metal poultry waterer bases that keep founts from freezing, and I came across a website that had directions for making your own. The person who posted it had LOTs of great pictures to follow along with, and made the heater from an auto oil drip pan and some type of heating pad that I believe he also said came from an auto supply store. He also recommended something called a thermocube which is an outlet plug that turns power on and off according to the air temperature. It would be much cheaper to build my own since I need 2 or 3 than to buy that many, but of course now I am searching and searching and can't find the directions anywhere! Can anyone point me to right place??? Thanks!