This image, which I made a few years ago, is based on a tiling of the hyperbolic plane with triangles whose angles are π/2, π/3, π/7. Other than the 7, which can be changed to any higher integer, I couldn’t vary these numbers without ruining the effect. Recently I thought of a simpler, and thus more general, way to generate the ribbons.
A space-filling path through this square is matched to an analogous path through the color-cube.
I had this idea in mind for years but the algorithm for Hilbert’s curve defeated me; then I stumbled on Steve Witham’s Python code, and whipped up this doodle in half an hour.