i just think its cool, not very practical(at this time, might be in the future) I think its a very cool tech that is going to change how alot of things are done.
I heard NASA is working on a Pizza 3D printer..the pizza is just an easy first try because of it's shape.. But it seems it will run from bottles of nutrients that have an extremely long shelf life, even after installed in the printer. So it might be cost savings..no waste or spoilage. No word on if the product will support human life yet....
And a lot of variety might be possible for a journey to, say, Mars or beyond.
http://www.fedtechmagazine.com/article/2013/05/nasa-wants-fuel-astronauts-pizza-3d-printer
Lets just call it what it is, a "replicater" .

Here's the thing though, it's "multi media".
You use plastics and make a gun or wrench, use nutrients and print a pizza , where is this going ?
Put in some DNA and print someone a new heart or kidney ?
How about building a really big one to print a ship, or plane ?
One question about the material, after a project can you take the material that did not become part and reuse it ?