This is a series of short movies that use computer-generated animations to help visualize higher dimensional spaces. You start out looking at the plane (2D) from 3-space, and then try to look at 4-space, using similar tools of projection.
Even if you’re not mathematically inclined, you should find the first 4-5 of these movies to be intriguing and even beautiful. By the time they got seriously into complex math, my head began to hurt. They intend to continue on to chaos theory, dynamical systems, and topology next.