3D Printing's Next Revolution: Linux
3D printers may be trendy, but they are hardly new. One of the earliest of all is the RepRap project, which began back in 2005. As its name implies - it's short for "replicating rapid" prototyper - RepRap is designed to be able to produce copies of itself, or at least most of its parts. Not only that, it is completely open source, both in terms of its hardware (which uses Arduino kit) and software.
Because of its open nature it has gone on to form the basis of many other 3D-printing systems, including those from MakerBot.