Open Source Job Board Application: JoobsBox
JoobsBox is an open source job board application which is built with PHP (Zend Framework) & MySQL.
No membership is required to add new job listings & they can be posted under pre-defined categories.
It comes with a plugin system which makes it possible to extend the application easily. There are already several plugins like iPhone plugin or the Twitter plugin (auto-posts the listings to Twitter).
The application offers an admin panel where all the categories, listings, plugins & other variables can be controlled.
JoobsBox is multilingual & themeable. The project is currently in alpha stage, not mature but promising.