The S*ite M*anagement A*nd R*esource T*oolkit is a CMS designed as a platform to quickly launch basic website AND serve as a platform for further custom dynamic scripts. It has been in use in various forms for almost 5 years.
It's structure is setup so that other PHP based projects can be integrated by writing a "handler". The content can be stored in a MySQL database, html files, PHP scripts, or any other container that a handler is written for.
A unique feature is that it uses the database to store meta data on all the pages, however, it will automatically fall over and load static cached versions of the pages in the event the database fails. Dynamic (database) pages can also be specified to be loaded from cache intentionally to cutdown on DB lookups and improve performance.
Other integrated features include basic RSS, Calendar, "short cuts" which are user defined keywords that can be used anywhere in the system - in dynamic or static content or the template - to refer to images, links, pdfs, etc.
There is a user management system, which allows for in-line editing of pages, along with the ability to roll back to older versions of a page (the rollback feature is an extension of the off-line caching system, so it is easy to get a pure HTML version of any page.
A secondary security system is included for basic password protect of individual pages. This exists outside of the user system as a security precaution.
The directory structure specified via PHP constants, so that your content can be stored OUTSIDE of the document root, and privileged content can be invisible to unauthorized users (since the path would not be loaded without proper credentials).
It uses MySQL, and its schema allows multiple sites to be run from a single database making backups easier for multiple sites. Addionally, that structure optionally allows for multiple sites to be managed from a single install (which is a feature designed to make maintaining multiple sites much easier.)
These details are provided for information only. No information here is legal advice and should not be used as such.