I love a cool robot as much as the next guy, but a lot of these "building of the future" technologies act like they've won the race after the first lap. Prefab houses don't just give you the basic structure, they give you a finished house, with flooring, cabinetry, wallpaper, plumbing, electric... it's like the difference between a 3d printer that can print some of its rigid components and one that can print its servos and control circuits.