As 3D printing progresses, and so does the niche market of countour crafting, the possibilities of building structures on the Moon or even Mars increase substantially. NASA, and the ESA are working on ideas to 3D print a base on our Moon.

http://3dprint.com/3d-printing-of-mo...soon-possible/

Although the idea seems like sci-fi, it actually could happen within a decade. What are your thoughts ?