I had the great fortune to get my start programming as an REU for George. We were visualizing non-Euclidean spaces in VR, in the UIUC CAVE around the turn of the millenium. He also had an animated (minimax) sphere eversion with special audio cues that would play when interesting things happened. His website is still up, and I think some of his more recent REUs have been working on WebGL versions. Only about 5 percent of the math stuck, since I was not a math major, but I really came to appreciate affine transformations.

This is a book I keep recommending as well. It is very fun (and also includes a sphere eversion).