Giving back to the community
Not a regular contributor to only one project, I sometimes use reverse-engineering skills to dive into codebases of open-source software I use to fix what ails me. Then I submit my modifications as a "patch" to the projects' owners for integration.
KKRC dotfile management tool
This script provides better way to install and maintain vimrc, screenrc and zshrc files on unices.
Zend Framework (PHP framework)
Better lighttpd rewrite rule
vTiger (CRM system)
Various bugfixes
Better I18N code (sprintf-based)
WebService client library update functionality
Meatball Wiki (wiki engine)
Bugfix regarding page cachingVim (programmer's editor)
Patch to temporarily toggle the case sensitivity in search
MySQL plugin for "netrw", to directly edit database content (not released)
Battle for Wesnoth (game)
Multiplayer end-turn notification
Feng Office (project management system)
Minor fix to the RSS feed generator
ELKS (embedded Linux kernel)
Usage of a HGC/MDA monitor
OpenBSD (super-secure Unix variant)
Bug report
Slash'em (game, a Nethack variant)
Bugfixes (regarding path-finding movement)