A visualization for the irrationality of pi by rendering r(θ) = e^θi + e^πθi using 2 pendulums and demonstrating pi's irrationality through the fact that the pendulum never repeats the same path.
Here's an image of the program (https://randomgamingdev.github.io/The-Irrationality-Of-PI-p5js/) (you can control the speed with your scroll wheel):