Everyone is already all over this whole 3D printing thing. But 3D painting? It's a much emptier field. GE is experimenting with such a technology called "cold spray" that slowly builds up layers of metal by spraying metal powder at extremely high velocities. Instead of recreating works of art, the process is used to repair worn metal components, adding years or potentially decades to their life span. Unlike 3D printing which is severely limited in the size of the objects it can create, 3D painting is only limited by the spread of its spray. That means it could potentially be used to create or repair large structures, and not just prototype scale models of them. In particular, the process is being looked at as a way to repair parts used in oil and gas drilling. It could even be done on the scene and, unlike welding, there's no heat involved -- so there's very little chance for a fire or explosion. (And who wouldn't like to make our gas and oil wells safer.) For a quick demo of the process, check out the video after the break.