From the official e107 website e107 is a content management system written in php and using the popular open source mySQL database system for content storage. It's completely free and totally customisable, and in constant development.

e107 is a content management system written in PHP and using the popular open source MySQL database system for content storage. It's completely free, totally customisable and in constant development.
what's the difference between plugins.e107.org and e107forge.org?
The difference is the audience, while plugins.e107.org is aimed entirely at the end user who wants to be able to find a plugin easily and isn't necessarily interested in the code behind the plugin. On the flipside,
e107forge.org is all about the code and the developers, SVN and CVS access is available while providing a fully featured, easy-to-manage project page and allowing coders to collaborate together to work on a plugin. Rather than one developer writing a plugin and then another user making code changes and re-submitting the plugin, we can have collaborative developers drawn together by a particular plugin.
If you're a developer wanting to get your code or project online but need some help along the way e107forge.org is here to help. If you're a theme developer who's keen to have a versioning system take care of the headaches of making minute changes here and there, e107forge.org is for you. We can provide SVN and CVS versioning control as well as bug trackers / issues / feature requests etc. It really is up to you when it comes to which features you want to use.
Download:http://e107.org/edownload.php
Demo:http://opensourcecms.com/index.php?option=com_content&task=view&id=133