I use the Ranco for my fermentation freezer and I love it. Super easy to hook up as well. Here's the link for the controller and I'm pretty sure it's the same guy I got both of mine from: http://www.ebay.com/itm/RANCO-ETC-111000-DIGITAL-TEMPERATURE-CONTROL-120-240V-/120586443603#vi-content...
I was putting my used grains from steeping into them and sending the buckets with grain in them to my buddy who had chickens, which he fed with the grains. I've also used them for yeast starters. If you just have way to many to use, then maybe someone on freecycle would like them.