Much of the open-source code I'm involved with is available through http://github.com/nickludlam.
A system to subscribe a MythTV system to websites which provide regular recommendations. Mythrecommend regularly parses the website, extracts program information, and sets up new recording schedules within MythTV. It also sends emails out detailing what has been scheduled to record, and what is now available to watch.
An open-source video player for the Nintendo DS. It comes with a cross-platform encoder for Windows, Linux and Mac OS X, based on ffmpeg.
A Ruby Gem that allows communications and interaction with a MythTV server. It includes the ability to list and stream recordings, list the EPG, and create/edit recording schedules.
A simple RubyCocoa app I wrote to demonstrate the functionality behind ruby-mythtv, my Ruby Gem which allows you to interface with a MythTV Backend server.