A post on Mashable describes the goings-on at NASA where they're deeply investigating the possibility of using 3D printing technology on future space missions.
As we've said before, 3D printing in space could be massively beneficial, as you'd need only bring the printer and some print media with you into space, where you'd simply make any object required.
However, there are significant challenges, not the least of which is safety. But they're working on it.
Recently they've been investigating the use of 3D printing for building components for the new Space Launch System, or SLS. The idea is straightforward: 3D printed parts can be much lighter than conventionally manufactured component because the additive process permits production of more efficient geometric shapes. They're using metal 3D printing technology from Concept Laser to produce engine parts.
If you think this is science fiction, think again. With the announcement of Planetary Resources' plans for harvesting asteroids, there will be quite a few 3D printers in space.