I just watched an episode of Grand Designs where these guys built a house in a couple of months from parts cut on-site and assembled by hand.
"Facit Homes first designs the house using a 3D computer model, which contains every aspect from its orientation, material quantities, even down to the position of individual plug sockets. The patented “D-Process” then transforms the 3D digital designs into the home’s exact physical building components, using a computer controlled cutter. These components are usually made from engineered spruce ply and are light and easy enough to then be assembled together on site. Since the components are produced on demand, costs are kept to a minimum and lead times are eradicated."