This reminds me of a gadget I got a couple years back from my Bro-in-law.. it is called a Holee Molee…. it is battery operated and is suppose to keep your holes from freezing shut. I suppose I should probably find this thing… I think this might be the year to actually test it out…
I looked around a little for one of the can with a copper tube but could not find anything other than a description of how it works, nothing about how to make one.