This, to me, is insanely cool. The RepRap project, based in the UK, has free plans and software for MAKING your own 3D Printer! Yes!!!
I had been toying with the idea of making my own 3D extrusion mill, but this is a much more efficient approach as you only use material that you need rather than obliterating that which you do not need.
It is not a task for the meek, however. There are parts to buy, circuits to solder, and the thing itself to assemble. Still - for the determined, what an amazing device. Many years ago I wrote a mechanical doctrine of cell style community interconnectedness and partial self sufficiency. The underlying premise was that if you had a prescribed set of mechanical devices within a small collective, there was almost no need that could not be met. Having a Mendel RepRap device would potentially reduce that number, or at the very least make the upkeep of said devices much more simple.
This is one I may have to set aside time and funds for, maybe this winter. Certainly intriguing!
Update: Well, trolling through Makezine.com tonight has been a gold mine. Here I find, in addition to RepRap mentioned above, CupCake CNC. I think I'm going to faint.