DURHAM, North Carolina (WTVD) -- The Helping Hands Project has spread to universities and colleges across the Triangle. Students use 3D printers to make prosthetic hands for children who need them.

The Penrose Triangle is as elegant as it is impossible—much like M.C. Escher’s drawings, it presents a two-dimensional illusion that the eye interprets as three-dimensional. The task of effectively ...

What I intended to do with my 3D printer, I can’t remember. I vaguely remember wanting to print big things, but I was unsure what those might be. More abstractly, I was hoping the printer might ...