3D? Feh. MIT has already moved on to 4D printing (video)@ 2013/03/01
"Essentially the printing is nothing new," Tibbits told the BBC. "It is about what happens after." So far the concept has been demonstrated with thin strands of plastic, which, once added to water, form into a predetermined shape, using energy from the absorption. Suggested future applications involve furniture, pipes, bikes and buildings. First, however, scientists will have to demonstrate the technology on a larger structure, of course, and they'll explore the possibility of other energy sources, like heat, sound and vibration.