Proof Designer, a java applet that writes outlines of proofs in elementary set theory, under the guidance of the user. It is designed to help students learn to write proofs. Proof Designer's approach to proof-writing is similar to the approach used in my book How to Prove it. An old Mac Classic version of Proof Designer is also available.
EDPlot, a Mathematica notebook that illustrates the epsilon-delta definition of limits.
Tess, a Macintosh program that simulates a four-dimensional version of Rubik's cube. It will run in OS 9, but not OS X. If you want to download the software and documentation, click here.