I may be going out too far on the math limb here, but I have found a small firm that makes wonderful mathematical models: I spent many happy hours in my adolescence (which was otherwise an utter

failure) constructing models like this, with Cundy & Rollett’s Mathematical Models

as my guide. My pride and joy was five cubes in a dodecahedron, with each cube

painted a different color. I just used card, though: this firm does it

with high-precision aluminum die-casting. Jeff Tupper, who runs the outfit

(they are called Pedagoguery Software Inc.) tells me he hopes in future to

produce all the interesting convex (5 regular, 13 semi-regular) polyhedra,

possibly the 13 semi-regular duals, too. After that, they may tackle

stellated polyhedra, which will be a real challenge… Hello? Are you

still reading? Hello?….