3D printing hit the news a few months ago when a man from Texas put 3D printing designs for a gun that could be made anywhere online. It caused a worldwide stir and was eventually taken offline, though hardly in enough time to prevent it from spreading or being copied. 

In the near future, the technology for 3D printing will become much cheaper as patents expire which allows more companies to manufacture products, though it's primary use will hardly be printing weapons. The technology allows people to print and design objects that can be used for modeling purposes or sold as products. A dramatic reduction in cost would make these printers available for local, if not personal, use within a few years. 

From The Atlantic

Once the key patents on 3D printing via laser sintering expire, we could see huge drop in the price of these devices, says Scott. This isn't just idle speculation; when the key patents expired on a more primitive form of 3D printing, known as fused deposition modeling, the result was an explosion of open-source FDM printers that eventually led to iconic home and hobbyist 3D printer manufacturer Makerbot. And Makerbot was recently acquired by 3D-printing giant Stratasys for about $400 million in stock, plus a potential $200 million stock bonus. That acquisition was a homecoming of sorts for Makerbot; Stratasys was founded by Charles Hull, who invented 3D printing via FDM, the very technology on which Makerbot was based.

Within just a few years of the patents on FDM expiring, the price of the cheapest FDM printers fell from many thousands of dollars to as little as $300. This led to a massive democratization of hobbyist-level 3D printers and injected a huge amount of excitement into the nascent movement of "Makers," who manufacture at home on the scale of one object at a time.

A similar sequence involving the lifting of intellectual property barriers, a rise in competition, and a huge drop in price is likely to play out again in laser deposition 3D printers, says Shapeways' Scott. "This is what happened with FDM," he says. "As soon as the patents expired, everything exploded and went open-source, and now there are hundreds of FDM machines on the market. An FDM machine was $14,000 five years ago and now it's $300."