The nerds are all excited about 3D-printing guns. I don't understand why they are excited about this, and they were not previously excited about making guns using existing machining methods. I think they are excited about "making weapons" now that "with a computer" is attached to the end.
There is now a Wiki trying to round up working, public-domainish CAD designs for 3D printed gun parts. They are trying to get a design for a completely 3D-printed gun. They apparently thing this will bring weapons to the masses, despite that guns are already readily available, and readily manufacturable with techniques more accessible than multi-thousand-dollar 3D printers that have poor resolution compared to machining and work in PLASTIC.
http://defensedistributed.com/http://www.extremetech.com/extreme/133514-the-worlds-first-3d-printed-gunSigh.
