It's an anaglyph that I drew using Java. View it with red-blue 3D glasses. It's an experiment with complimentary colors. Red has been replaced with cyan. Blue has been replaced with yellow.
This background shows 2 layers of a honeycomb (a solid tesselation) composed of octahedra and tetrahedra. This is the only "quasi-regular" honeycomb (see H.S.M. Coxeter "Regular Polytopes" section 4.7 (Coxeter01)). For other (more attractive) honeycomb backgrounds, see my home page and my Rhombic Dodecahedron Page.
-- Mark