I've also got an STC-1000 - which cost me $18, then another $12 in parts to build and wire it. Picked up a used chest freezer for $50, total cost: $80.00 for a fermentation chamber. As others have suggested, it only reads in Celsius, but it's nothing more than a superficial inconvenience.
Haven't needed to put a heat source in there since I have the freezer dialed to its lowest setting and only fluctuates a 1/2 degree.
I'm not liking the inconsistent readings from taping a temp probe insulated to the side of a carboy, doesn't seem to read as warm as I'd expect, probably because it's not near the center of the wort. I've got thermowells on order, those ought to be more accurate.