Sijio is a fast, high performance, easy to use and fully customizable PHP community script. It is equipped with all necessary professional tools and features to run a full fledged community site. Features include blogs, events, a forum, a gallery, polls, page management, user management, and RSS feeds, customizable Smarty powered templates, WYSIWYG editing of any content, easy picture upload, an unlimited number of attachments, and more. It is completely SEO friendly.
tilswiki is a wiki engine that is always in edit mode. Any user can always click in the content area and start typing. Its intention is to be the radically easiest possible publishing tool. Its feature include basic text formatting, image uploading, resizing, and positioning, HTML, security through unguessable page URLs, customizable page URLs, and email notification on changes.
AldoContent is a lightweight CMS focused on usability and simplicity. It is designed for multilingual Web sites and can have sections with public and private content. It has file management, is extensible with plugins, and uses gettext for localization. Is written in PHP for a MySQL backend.