I’ve written a few games you can play in your browser, which are listed in a page of their own.
For a few years, I was the project maintainer for Gnu Wget, a ubiquitous web-fetching tool for Unix. More about my involvement with Wget.
Another gnu project, authored and maintained by myself. Useful for decoding and understanding terminal escape sequences, and also for recording and playing back interactive terminal demos. Teseq project page.
My involvement with Wget inspired me to start work (but not quite finish) on an alternative implementation with similar features, but very different design, with a focus on easy extensibility. Niwt wiki.
Prompt Jobs is a shell script to insert abbreviated information about suspended jobs into your shell prompt. More info.
I wrote a printable PostScript file (also available in PDFs) that generates a new set of mazes to solve, every time you print it (in the case of PDF, every time you grab a new copy of the file).
Most of the projects mentioned on this page, and a few I haven’t documented or didn’t find noteworthy, can be found in my GitHub repository, or my local Mercurial repository. You can also check out my Ohloh page to see some of the other projects (not my own) that I’ve contributed code to (such as the Linux kernel, the Vim editor, and tmux).