The Street - It's called a printer but really is a manufacturing plant in a box. 3-D printers can build an object, layer upon layer, from plastic, metal, glass, ceramics – even chocolate. By now, we have seen that these amazing desktop devices can create guns, human tissue, DNA -- and drugs. As with most emerging technologies, for years 3-D printers were institutional and educational devices priced far beyond the reach of the typical consumer. Now you can buy one on Amazon. Creating your own plastic toy is one thing, but as the technology evolves, the world economy might face a physical hack from the same particle print-on-demand technology.