Fans of science fiction or just technology in general will be pleased to learn that 3D Printers have become so precise and easy to use that a man printed an AR-15 receiver. I've worked at a plant that makes firearms parts and current industrial tech for making a receiver is big, loud and messy and that is the biggest issue with making your own firearm. Technically the receiver is just the framework that holds all the other parts in place, but it is the most important part as well because an out of spec receiver means nothing else will fit and operate as it should. Legally it is also the part that is classified as a firearm and carries serial numbers on it. This might be the single biggest obstacle gun grabbers have ever been faced with due to technology, and I love it. However the gun rights issue is not the main point here.
3D Printers are part of a shift in manufacturing, along with nanofabrication, that is miniaturizing the whole process of creating parts in tight tolerances, and as that technology becomes easier to use and cheaper it's going to drastically decentralize the manufacturing process worldwide. Imagine a world in which your local computer store can fabricate and assemble your dreams machine in a matter of hours, it's going to be cheaper than ever before because delicate parts don't need to be shipped in special packing any more, just batches of raw material. It will even simplify storage since materials in bulk can be stored in simple, standard containers. Wait times on special orders at service locations (such as auto shops and electronics repair shops) will be a matter of minutes or hours to make the part from a licensed design, instead of days or weeks to send the order to the factory and then get a part shipped out.
Of course we aren't there yet, but every step there is a step closer to a changed economy, one less dependent on the antiquated infrastructure of yesterday and today and that means our leaders need to start thinking of how to build towards that bright tomorrow, not something that politicians are well known for. Congress is always fighting over the last issue, but here's hoping the next round will go better than the last.