Some of my projects:
TeXstudio: a LaTeX editor with grammar/syntax checking, pdf viewer and other things.
Pascal Internet Tools: A dependency-free Pascal implementation of a HTML parser, CSS 3 Selectors, a XPath 2 and XQuery 1 interpreter.
Xidel: Command line tool to extract data from html files and entire webpages (example project for the Pascal Internet Tools)
XPath 2/XQuery online tester: CGI-Version of Xidel
Q&A for professional and enthusiast programmers
Q&A for computer enthusiasts and power users
Q&A for users of TeX, LaTeX, ConTeXt, and related typesetting systems
Q&A for science fiction and fantasy enthusiasts
Q&A for people studying math at any level and professionals in related fields