This is a rework of an old image This image was presented last year in the German math exposition call IMAGINARY2008, here is the text joint to the image: A TRIPLY-PERIODIC LEVEL SURFACES The green-tinted surface pictured here has three orthogonal trans- lational symmetries. It is the level-surface given by the trigonomet- ric equation: 4*(cos x*cos y+cos y*cos z+cos z*cos x) - 3*cos x *cos y *cos z = -2.4 A unit cell may be viewed as a central chamber with tubes to the corners and faces of the cube. This surface closely approximates the minimal PW Hybrid Surface discovered in 1880 by Karl Hermann Amandus Schwartz (who was a Professor at Halle, Goettingen, and Berlin). Recently it has been investigated by material scien- tists, who use it and related surfaces to model so-called block- copolymers. The original model was taken from David A. Hoff- man. This was textured, placed in a scene that we feel adds to the beauty of the object and rendered in Bryce.