Ok, so the fact that they chose to print a gun as opposed to some other useful tool is probably mainly for shock effect and media appeal. Still, the fact that these guys are able to print high-tolerance metal parts is amazing! Click Here for the article.
3D printers are becoming more commonplace, but most of them use plastic as a medium and create output using layers of melted plastic (stereo lithography). Below is a MakerBot 3d printer.
This cool gadget can be yours for a paltry $2,899!
As you might expect, a device that produces metal parts is a LOT more expensive. Services like Solid Concepts can be very useful, giving you the ability to print on much more expensive gear, using more exotic materials for one-off manufacturing, prototyping, or even replacing impossible to procure parts on an existing machine! These folks actually have a firearm manufacturing license, so if you have a gun with a broken but impossible to find part, they can probably make it for you quite easily.
Inane World 
I don’t know whether it’s just me or if everyone else experiencing issues with your website.
It looks like some of the text within your content are running off
the screen. Can somebody else please comment and let me know
if this is happening to them too? This could be a
issue with my internet browser because I’ve had this happen before.
Many thanks