Thanks to Cavedave on Reddit I just came across a totally touching 3D printing story. It is back from 2000, but I had never heard it before. It is about a blind mathematician named Bernard Morin. He was interested in the topology of a shape he had invented versus a new version of that shape but he could not see the rendering of the new shape. Stewart Dickinson then printed out the shape with the help of 3D Systems so that Morin could feel the difference. Check out the pictures of the topologies and Professor Morin here.
It also makes you stand in awe at the brains of some people on this planet. Morin, can't see, and he teaches mathematics in Princeton. Hawking, who has no mobility now, can solve intense mathematical equations in his head. It's almost worth the sacrifices to be able to see what these two see.