3D printing in the near future.
In about three to five years from now, like we had DTP service guys operating with a few desktops out of a cubbyhole in the nineties, we will have 3D printing studios down the street where one could go with a hand-drawn dimensional sketch of her/his next big invention and get it printed in a few hours (depending on the size & complexity). In fact, everyday objects such as flower vases, utensils, paperweights, artefacts etc. could be printed at these studios. This would be the intermediate stage before 3D printers become a household possession like today’s deskjet printers.
3D printing in the not-so-distant future
When 3D printing gets in the mainstream and becomes capable of using materials which are of production quality, manufacturers would benefit the most as complex supply chains of components would get disrupted…. components would be 3D printed as and when required without having to be supplied from multiple vendors and stocked for assembly. Companies sourcing components from half way across the world would be smiling. Imagine the carbon footprint saved in terms of fuel spent on logistics!!!!!
NASA is aiming to send a 3D printer on its mission to the moon. That 3D printer would be capable of printing entire housing modules using lunar material, thus eliminating the need of carrying a huge payload of materials from Earth. Colonizing the moon is not a long way off 
Already, there are communities on the internet where geeks share 3D designs of various objects. Soon these communities will be flush with drawings of everything in the world and these geeks would be co-creating a host of new things. For all you know, drawings of all the 20,000+ components that make up a car would be available in these communities and ONE COULD PRINT THEM AT HOME AND ASSEMBLE IT IN THE GARAGE. The more I think about it the more convinced I get that this will happen. Remember the way computers were assembled in garages by amateurs four decades back……… with standard components available off the shelf in DIY outlets
But “What is 3D printing?”
Let us understand it without getting into any technicalities. When a normal desktop printer prints on your paper, the nozzle of the printer goes twice across the same line to deposit the ink on the paper and voila you see what you intended to print. This is conventional printing as we know it for decades. Now imagine if that printer kept on printing on the same line multiple times and kept depositing ink along that line on your paper, would it not begin to form a thickness along that line? Of course the paper would have to keep moving downward as the nozzle kept depositing ink on it OR the nozzle would have to keep moving upward as the printing progressed and voila again, you would be able to see a thick layer of ink on that paper of yours. The downward movement of the paper OR the upward movement of the nozzle is the additional dimension in printing……..that’s why it is called 3D printing. This is a very simplistic explanation of the 3D printing process. Imagine instead of ink the printer deposited a layer of material (plastics/ powdered metals with a bonding agent etc.) through the nozzle, one could print objects using drawing software modules that enable 3D rendering.
What can 3D printers do?
It’s a boon for tinkerers, who want to see a physical form of what they have in mind. A 3D software module such as Autocad, ProE, Catia etc. Making a prototype otherwise involves some fabrication, the infrastructure for which is not always easily available. With a 3D printer around, all that one needs is a 3D rendering of the object that one wants to prototype. For large companies, it eliminates the necessity of making a mould just to prototype, thus reducing the cost and time-to-market.
The cost of 3D printers is falling drastically. The cheaper variety is about USD $1000. Some are even lower, however, the quality of the objects printed on such printers is quite patchy. Good quality printers still cost a bit and that’s what will keep them out of bounds for the common man for a few more years. However, as mentioned above, till then we will have to make do with 3D printer studios down the street 
