The Inverse Graphing Calculator
The Inverse Graphing Calculator was written over a weekend when I was first dabbling in basic LAMP-style web development. It promptly went viral, and has continued going viral every now and then ever since. Enter an English phrase, and the IGC will generate a mathematical equation whose graph spells out that phrase on the xy-plane.

Productivity software webapp focused on recurring tasks with no fixed deadline. You enter tasks, enter a rough estimate of how often you'd like to do that task on average. Any time you log in and look at your tasks, you'll see them sorted based on urgency.

Patterns of Resemblance Calculator
A sophisticated engine for performing calculations on geometric data structures called patterns of resemblance. Patterns of resemblance notate ordinals up to the ordinal of PI11-CA0. Some of the algorithms implemented in this engine are original and were printed in the Archive for Mathematical Logic.