3D printing is in the news pretty frequently but there's an aspect of the development which, for me, is much more significant and hasn't got a great deal of recognition. This is the Open Source revolution and how amateurs have largely developed a complex technical chain, and shared it freely with anyone who comes along. (The Raspberry Pi too started life as an open source development before being productionised by Farnell.)
I've written before about amateur technologists, Tinkering-on-cutting-edge Photography, radio and even rocketry developments were initiated and to some extent developed by amateurs spending their own money and time. Of course, eventually these technologies were grabbed by big business, who took the profits after the enthusiasts had shown what could be done.
The difference now is Open Source, and the availability of the internet to allow the quick sharing of software. The 'net is full of discussion groups and file sharing areas where all kinds of information is being disseminated. With 3D printing another aspect is possible, mechanical parts too can be shared. Download the 3D .STL file from one of the file sharing sites like www.thingiverse.com/ and you can be 'printing', making a part, in minutes.
A 3D printer, such as mine, uses the extrusion method to produce a printed part. Other 3D printer technologies exist but this one is the technology most suited to amateur use and development. Even so the path from 3D drawing to printed part is a long one. As Adrian_Bowyer says, the 3D printer brings together the technologies of mechanical engineering, electronics and software. Bowyer would, if there were any sense at all to the British honors system (which seems to specialise in honouring 'celebrities' and business men), already be recognised for his contribution to this nascent technology.
Now you can be sure that Big Business, Made in China will be along soon enough but 3D printing isn't quite ready to be rolled out in Medi Mart, but it will be. My guess is that by this time next year 3D printers will be on sale to the masses and, likely, the first ones will be in the kitchen printing chocolate.
Big business, of course, doesn't like risk. If it's going to go there at all it would, ideally, like the tax payer to fund it. And preferably after having someone else prove that the basic concept is viable. In Britain jet engine development was pioneered by Frank Whittle, an enthusiastic amateur who tried, in vain, to interest the big British engine manufacturers in his invention. It was only after Whittle himself had a jet engine running and, thanks to the war, generous public funds being available, that private industry, rather reluctantly, got involved. Things were different in Germany and happened quicker, the Nazis were quicker to fund new technology. On both sides though, amateur development and public funding, front ended a whole industry which eventually made huge, private profits.
With 3D printing academics like Bowyers and an on-line army of enthusiasts have been doing the grunt work. Now, all the engineering is available for anyone to build and, for those with the skills, to copy and modify. See http://forums.reprap.org/
Recently Elon_Musk, the man who made a fortune with PayPal, declared that by patenting a technique you were effectively providing Chinese industry with a free recipe (therefore he wouldn't patent the new welding technology of the space launcher project he is developing). Of course, Big Business, in persut of profits today, is busy sharing all the existing techniques of aerospace and auto engineering with the Chinese. And paying them to learn how to productionise it. They don't actually have to steal much.
But with the 3D printer it's a little different. All software, in source form, is available. Many of the mechanical parts can be printed. In this case there's no way to steal it. If you give something away how can it be stolen?
Sharing is a very ancient social model, 'to each according to his needs, etc.' wasn't just a slogan but the way many of the ancient hunting societies worked. If you had had a good day you shared with the rest of the community, knowing that tomorrow, or next week you'd be hungry again and this time, perhaps, unlucky. Sharing may also be the essential drive behind art, 'this is what I made, look at it'.
If the design is there on the net, it remains in public ownership. True, Big Business may yet tame 3D printing and streamline the user interface but the Open Source basics will still be out there. Maybe this will be a game changer? The old model, pioneered and developed by amateurs, the Wright Brothers etc. profits made by Howard doesn't end there.
For a possible extrapolation of the technology 3D printing see Neil Stephenson, The Diamond Age.