Part of my job is to design objects that will be used in a high-magnetic field environment, namely MRI scanners. Metal is not an option for me. Prototyping with traditional methods (e.g., CNC machining) is extremely cost-prohibitive.
So I use 3D-printing. Some I do in-house with an FDM machine, in ABS. A lot I outsource to a better printer that can use other materials, say polycarb, or other methods, like laser sintering. At the end of the day, I get functional prototypes that I can check for utility, than design molds for injection-molded parts based on feedback from those prototypes.
3D printing enables me to do this part of my job. Without it, there would be no prototyping, due to cost, and thus no objects in the magnetic field. Truly a gamechanger.