Projection perspective

thingiverse

The idea is this shape has a simple, different (symmetric) cross section from three directions. I've seen textbooks try to convey similar ideas on a 2 dimensional sheet of paper and wanted to make something you can hold to make the idea more clear. You could also shine a light on each face to "project" each shadow on the wall or print in a glow in the dark material. Feel free to use it in any way you like.