Go to wikipedia (or your favorite search engine) and do a search for free content management system. Some of the first ones that come to mind are tinycms, mkportal, dragonfly, impresscms, typo3, MDPro from maxdev, phpnuke, and CMS Made Simple. Even though there are a lot of CMSs out there, you really need to be careful. A lot of the older projects are just about abandoned and rarely get updated. If you want something that stays updated, flexible, and secure, then go with either wordpress or drupal.
Check out opensource directories and toplist - you'll find plenty some of the recent up comers are Magento and Prestashop (personally I like prestashop better than Magento)
Is there any reason why you're looking for something else instead of using the CMS that you've mentioned? Joomla and Wordpress have wide user based so it's easy for you to get help if you have any problem in the future. But you can find list of other CMS here : http://en.wikipedia.org/wiki/List_of_content_management_systems#PHP_2 - Dynashox -
I had to do an evaluation of a few CMS packages and for me the one that came out on top was CMS Made Simple. Easy to use and you can do some pretty advanced stuff.
Joomla, wordpress or drupal are the best would be nice if you learn them, so you can build your own framework