Drukkar is a lightweight blog engine and CMS written in PHP 5 with no external dependencies. It supports Markdown, generates clean and valid HTML, and stores individual posts in XML files. It doesn't use a database.
qb is a blog system for people who don't want to install a database server, but want performance and like to be able to send entries via SCP, cron jobs, or other obscure methods.
A desktop Java application framework.
Asymetric file encryption using Curve25519.