I finally got lucky and found a mini fridge on craigslist without a freezer. Using a box cutter, I hacked off the door frame leaving the part that has the screw holes in it. The fridge fits two 3-gallon carboys pretty well, and should fit a 6-gallon Better Bottle if I can find an airlock alternative or use a blow-off tube.
Currently hooked up to a Johnson Controller fermenting at a nice 60 degrees.
Also fits a corny keg for loggering, or could be used as a kegerator.