There's a 3-D revolution coming that could alter the world we live in, with 3-D printing machines that can make everything from a chair to a heart valve. But how about this -- you could also push a button and "print" a gun...a real gun. This is not hypothetical; 3-D printing is here, and it works. Madeleine speaks with tech guru Andrew Lih, new media director at the USC Annenberg School.
The image associated with this story shows a 3-D printer, though not necessarily the kind capable of making gun parts. (Credit: devopstom/Flickr/Creative Commons License)