RepRap: Replicating Rapid-Prototyper.

The RepRap project is working towards creating a universal constructor by using rapid prototyping, and then giving the results away free under the GNU General Public Licence to allow other investigators to work on the same idea. We are trying to prove the hypothesis: Rapid prototyping and direct writing technologies are sufficiently versatile to allow them to be used to make a von Neumann Universal Constructor. (...) A universal constructor is a machine that can replicate itself and - in addition - make other industrial products. Such a machine would have a number of interesting characteristics, such as being subject to Darwinian evolution, increasing in number exponentially, and being extremely low-cost.

A rapid prototyper is a machine that can manufacture objects directly (usually, though not necessarily, in plastic) under the control of a computer.

An experimental prototype at LinuxConf Australia 2006:

Check the work in progress on the reprap blog.

The quotes gives some ideas of the scenarios:

I have no need to buy a spare part for my broken vacuum cleaner when I can download one from the Web; indeed, I can download the entire vacuum cleaner. Nor do I need a shop or an Internet mail-order warehouse to supply me with these things. I just need to be able to buy standard parts and materials at the supermarket alongside my weekly groceries.