writes "Star Trek has the replicator that can make anything out of its constituent molecules. It isn't Researchers at the Massachusetts Institute of Technology are trying to push 3-D printing technology further. Their goals: create whole working machines and perhaps even buildings. Thus far, 3D printing technology has been used to make shapes of plastic or metal that can be assembled later. These folks want to change that.
One idea is to make concrete whose properties vary through the structure. That would allow the building to flex where necessary, while maintaining its structural strength. It would also allow for lighter structures."Link to Original Source