I've just discovered the animations of one John Whitney, who built an amazing analog computer and used it to make moving geometric patterns. When digital computers started to become available, he used those as well.
Of the movies I've seen so far, I think Permutations is my favorite. It looks like it's made of hypocycloids, which is exactly what I've been tinkering with myself, all summer, so it has a pleasing familiarity. I'm making a mental note that I need to start learning how to make animations. And also a quick sketch, because those are more easily remembered than mental notes.
untitled [after John Whitney]