I love emmett's folding cubes. But with my kids they get played with so much that the hinges don't last long. This is a simple hack to replace the cone and socket hinge with holes for hinge pins. The finished cube is comparatively indestructible.
I printed at 125% in Makeware, then drilled the holes out just a tiny bit to 3mm. This is convenient as I have a large quantity of old 3mm filament. After assembly you can lock the pins in place with a soldering iron.
You can learn more about this thing and others like it on "3D Printing Today" the podcast available on iTunes, or Stitcher radio or right from the source at http://threedprintingtoday.libsyn.com/