I've had some access to 3D printing lately and have heard there are some 3D printed metal stuff coming out but I think that the place it will be good is in making plugs for molding. You can get some pretty fine tolerances with new machines.
Made Boards in America are trying. There is not much on the board on their web site, but if you can be bothered watching the videos they say it will be the next big thing. The prototype board looks a bit average though.