WordPress
WordPress is a blog script and a personal publishing tool with focus on aesthetics and featuring cross-blog tool, password protected posts, importing, typographical niceties, multiple authors, bookmarklets.
Homepage: http://wordpress.org/
WordPress support forum
b2evolution
b2evolution is a blog script featuring multiple blogs, categories/sub-categories, skins, search function, multiple languages, search engines friendly URLs.
Homepage: http://b2evolution.net/
b2evolution support forum
Joomla
Joomla! is one of the most powerful Open Source Content Management Systems on the planet. It is used all over the world for everything from simple websites to complex corporate applications. Joomla! is easy to install, simple to manage, and reliable.
Homepage: http://www.joomla.org/
Joomla support forum
Drupal
Drupal is An advanced portal with collaborative book, search engines friendly URLs, online help, roles, full content search, site watching, threaded comments, version control, blogging, news aggregator.
Homepage: http://drupal.org/
Drupal support forum
phpWebSite
phpWebSite is a very powerful Content Management System with document manager, announcements, menu manager, photo album, block maker, FAQ, web pages maker, polls, information categorizer, calendar, link manager, form generator.
Homepage: http://phpwebsite.appstate.edu/
phpWebSite support forum
phpBB
phpBB is a widely-popular open-source bulletin-board package, works well, simple user interface and admin panel, clean look, scales well, and can be customized.
Homepage: http://www.phpbb.com/
phpBB support forum
SMF
SMF (Simple Machines Forum) Elegant. Effective. Powerful. Free. SMF is all of the above. SMF is a next-generation community software package and is jam-packed with features, while at the same time having a minimal impact on resources.
Homepage: http://www.simplemachines.org/
SMF support forum
Coppermine
Coppermine is an Image Gallery system featuring categories and albums, thumbnails and intermediate size pics, search feature, new and random pictures, user management (private galleries, groups), user comments, e-cards feature, slideshow viewer.
Homepage: http://coppermine.sourceforge.net/
Coppermine Photo Gallery support forum
