Yes, it's essentially "free" - an electrical heater does the same thing as a computer in this regard. My MacPro3,1 (lovingly called The Behemoth) produces enoug

Yes, it's essentially "free" - an electrical heater does the same thing as a computer in this regard. My MacPro3,1 (lovingly called The Behemoth) produces enough heat to make my home office comfortable through most of the winter. The electrical bill is astronomical, however. And it really sucks in summer. I always wondered why data centers aren't exporting heat to the local community the same way many power plants do - it's a lost opportunity. It would also be a great secondary heat source for many skyscrapers if they designed them with a well-placed datacenter inside.