http://feindura.org/

feindura is a flat file based Content Management System written in PHP, which doesn't need a database. Just create your layout, integrate feindura in your website, upload it to your server and you're done.

https://sourceforge.net/projects/ezadmin/

http://esitemaker.sourceforge.net/

Elemental Site Maker elementalSiteMaker is PHP based easy CMS, with strong object-oriented architecture.

https://sourceforge.net/projects/easysitebuilder/

https://www.dynpage.net/

DynPage allows you to edit Websites online and make pieces of contents editable with a comfortable editor. DynPage implements the CKeditor - one of the best Internet editors.

https://sourceforge.net/p/dorncms/home/DornCMS/

https://cutephp.com/

http://www.cmsimple.dk/

CMSimple is a CMS (content management system) designed primarily for the creation and maintenance of small sites, easy for commercial, personal or association websites. It is small, simple, smart and easy!

https://www.cmsmadesimple.org/

CMS Made Simple, an open source content management system, allows for faster and easier management of website content. This CMS is scalable for small businesses to large corporations.

https://textpattern.com/

A flexible, elegant, easy-to-use content management system for all kinds of websites, even weblogs.