I think it's worth considering the usefulness, or not, of the heat generated. In the summer, you have to pay for the GPU to heat the closet and then pay for your air conditioning to get the heat out of your home. But in the winter the heat offsets your furnace. While the electric cost is probably higher than central heating for the same unit of energy, it does add to your profit. The $10 in electric cost may have saved you $5 in natural gas.
The year is 2150 and you're traveling through the nuclear winter wasteland, searching for somewhere to settle that's safe from the packs of feral self-driving cars and rogue delivery drones. Inside a derelict Amazon fulfillment center you come across a group of silhouettes huddled around a crypto miner for warmth, drawn in like moths to a flame by the steady rainbow pulse of RGB lighting emitted from the old gaming rig.
