Here's how it looks cut in half.

This radiolarian-like object is really a Voronoi network with the symmetry of a snub cube.  It's fairly convincing I think, considering that no real organism would be likely to have this symmetry.

This model came out of such an odd grab bag of tools that it deserves a technical note.  To make it I began with some points arranged on the underlying symmetry, then used Qhull to find their Voronoi cells.  I wrote some little Perl scripts to add thickness to the lattice of cell edges, then used ZBrush and Surface Evolver to subdivide and smooth the mesh. 

Vorocube metal print, 3 1/2" diameter - $370

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