cloc counts blank lines, comment lines, and physical lines of source code in many programming languages.

Hosting git repositories -- Gitolite allows you to setup git hosting on a central server, with very fine-grained access control and many (many!) more powerful features.

rc file (dotfile) management

The book documenting the curl project, the curl tool, libcurl and more. Simply put: everything curl.

converts nroff man pages to HTML

greple: extensible grep with lexical expression and region handling

Posting script to Hatena Diary ( http://d.hatena.ne.jp/ )

transaction logging in JSON, within the MySQL database