Depends on the residence. I have personally seen a large house in Brooklyn with dual 200 amp 120/208 volt three phase services (two meters, each feeding a panel.) I have seen someone setup an old SGI rack scale Origin 3000 systems in their garage. I think they even had an electrician upgrade their service to accommodate it.
100% this. But don't forget the garden hose running full blast so you can cool it! It's not impossible to get up and running for fun for an hour, but this isn't a run 24/7 kinda setup any more than getting an old mainframe running in one's garage is practical.
