PHP Easy Ticket System is a full blown help desk application that you can use for support, reports, errors, feedback, or a help desk. It has administration control and users can check how their tickets are coming along.
Gestiolus is a very simple Web application system for managing repair work. Written to be used in a school, it can be easily adapted to other employments.
An RPG action adventure game.
A full featured file system for Amazon S3 and other online storage services.