Icosahedron
thingiverse
A parametric icosahedron made with OpenSCAD's polyhedron() function. It is more an exercise in math. Probably not printable for a variety of reasons (overhangs, probably hollow). Taken from: http://en.wikipedia.org/wiki/Icosahedron#Cartesian_coordinates If you want a solid (read "working") one, try: http://www.thingiverse.com/thing:65709 If you want a mathematical model of the icosahedron, download away.
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