Shapeways offers several different processes. The lost-wax stuff is for jewelry, so you can make hollow objects in expensive metals. Laser sintering is used for working parts. There's also MarkForged [1], which has their own process for 3D printing carbon fiber and metal with a sub $100K machine. It's kind of slow, but they're selling it to make dies for injection molding.

[1] https://markforged.com/