MIT’s discovery may replace 3D printers. What?

If the Massachusetts Institute of Technology (MIT) has its way, 3D printers may also be a thing of the past. When it comes to 3D printers, most of them either deposit or fuse in-place material into solid objects. However, MIT has come up with something out of the box. The institute researchers have conducted an experiment that involves a massive vat of "smart sand". These objects are controlled by a microscopic computer and in theory would be able to self-assemble into desired 3D shapes. All this resembles the scientific fiction "object copier".
And how all this is done? What is required is incredibly smart and efficient software algorithms that control grains, more specifically, their movements and magnetic control points. Once the algorithms are at place, the grains communicate to each other using short-range networks to coordinate their activities.
However, there are various issues with the applicability of such an invention by MIT. For instance, how robust would be an object made up of grains for that matter. But it is safe to conclude here that the technology is worth to keep an eye on in the near future.