I just finished racking my second batch to the secondary fermenter, and I've noticed that the only truly difficult thing so far (besides waiting until the beer is ready) is controlling the temperature. I live in an area where the temperature varies dramatically, and I need a system that will handle both heating and cooling to keep the fermenter at the right temperature. I also need it to be inexpensive. I was considering trying to rig something with an arduino board, a heating belt, and some peltier coolers, but that would require a lot of work. Are there any cheap solutions available? I don't mind building something, but I'd prefer buying something off the shelf if it's cheap enough.