Stretching the boundaries of the “math” category, I’d like to point you to Bathsheba Grossman: an artist who makes stunning sculptures based on (amongst other things) mathematical operations.
The Vorocube - a tangible Voronoi network.
Should you find the time to browse her site, you’ll also find quite interesting 3D laser etchings in glass. And no, it’s not the tacky stuff you can buy at the mall - it’s really worth a look.
[Edit - fixed spelling]