Comment Doesn't seem like it would be worth it, but... (Score 1) 90
The price of the hardware would make ridiculous to just shut your miner off when it's not cold, so you'd only get this heating benefit for a part of the year and still have to cool it the rest of the time. Also, as has been said elsewhere, gas or a heat pump would be more efficient.
I wonder if anyone has tried this as an electric pre-heater for hot water though. A closed liquid (oil?) system that pre-heated a water tank that supplied your electric instant-on hot water would be able to run year-round. Adaptive CPU speed could slow it down as the water temp reached a level too high to properly cool the CPUs. The oil could also be circulated to heat the house in the winter or heat a pool in the summer.
If you were already using electric to heat your water, nothing lost--I don't think there is a "More efficient" electric water heater that leverages electricity and ambient temperature the way heat pumps do--at least not that I've seen on the market.
Seems too obvious, I'm guessing the actual implementation is much more problematic than it sounds.