I currently spend my free time on my company, the game mod Project Ironfist, and the Revitalize toolchain behind it, but I've done a lot over the years. I wrote my first Firefox extension before I became a Firefox user, and my first Facebook app before I became a Facebook user. A lot of my past work since 2007 is on Github, but I'll highlight some here.
Pardus is an online space-trading game inspired by Elite and Master of Orion. I started playing in 2004, when I was 12, and within a year had written several tools used by thousands of players, growing to around a dozen over the next few years. Many I kept secret within my alliance, some I released on my old website, one is hosted by the game's developers, and one I was hired by another player to create. They include a few Greasemonkey scripts and another player's spreadsheet that I took over on the low end, three Firefox extensions on the high end, and countless Java GUI apps in between.
Mao is my favorite card game, but, as a game about making up new rules, any system that can play it online must be able to play any card game -- no, any game. How do you do it? I spent much of my senior year of high school answering this question. Here is the result.
Are You Thinking What I'm Thinking
Somewhere between The ESP Game and the Newlywed Game, in this Facebook app, two friends answer questions and predict each other's answers. I built this with my close friend Jonathan Paulson in December 2009 for a competition to create the most popular Facebook app in 60 days, sponsored by polling startup CivicScience. We won the $3000 grand prize by a large margin, receiving the comment "The idea itself is worth money."
We've signed over the rights, but, as of November 2011, they've been rewriting it in PHP (from Clojure), and hoped to release it within a few months. Stay tuned.