Welcome to the AcdBrn CMS. This is a project that I started working on back in 2005. Over the next few years I made many updates to the system while working for an employer as well as various side projects. The system started off as my first introduction to PHP and MySQL, and spiraled out of control. It really was never intended to get as big as it did, and like all short minded projects, suffered accordingly.
I mostly keep this around for historical purposes. It is almost entirely procedural code. Don't let the recent dates fool you; this code wasn't written during 2010 and 2011 (save for some slight updates to make it easier for others to understand).
If you are looking to learn PHP and don't know much about objects, this might be a decent starting point. If you are looking to use a decent PHP CMS or framework, run far away!
The most notable project using this CMS is whitetailworld.com.