How to keep jerry cans from freezing when boondocking?

Wow! Steve, great idea! Now for the inevitable questions. First, would you consider taking photos of the project and posting them on the DIY forum, perhaps with some explanation of the circuitry? Second, does this system cycle on and off during the night, and does it make a lot of noise? I would put up with a little noise, in return for keeping the outlet pipe from freezing. Thanks in advance -- this device could make a big difference for everyone who likes cold weather camping (and don't we all?). ;)