There are a number of pilot projects currently in development to heat entire neighbourhoods using the waste heat from data centers.

Unless you've got a monster ML workstation under your desk or a crypto mining rig in your garage, that surplus heat isn't especially useful and isn't really worth harvesting. A typical desktop PC only dissipates a few tens of watts at idle or a few hundred watts under heavy gaming loads, versus many kilowatts for a typical domestic water heater.

https://www.gov.uk/government/news/thousands-of-homes-to-be-...