Last update=10 Nov, 2017
Julia Sets, software for constructing fractals in the complex plane -- Julia sets and the Mandelbrot set (updated Feb 15, 2018).
Groups & Graphs, software for graph theory, automorphism groups, torus embeddings, projective plane embeddings, polyhedra, and much more. (updated Aug 11, 2017).
Planets, software for investigating the n-body problem -- constructing planetary orbits and choreographed orbits.
Polyhedra, software for drawing and transforming polyhedra in 3D and 4D, and constructing convex hulls.