TikiWiki CMS/Groupware is a full-featured, web-based, multilingual, tightly integrated, all-in-one Wiki/CMS/Groupware, Free Source Software (GNU/LGPL), using PHP, ADOdb and Smarty. It is actively developed by a very large international community and is translated in over 30 languages.
TikiWiki can be used to create all sorts of Web applications, sites, portals, intranets, and extranets. TikiWiki offers a very large number of features "out-of-the-box", arguably more than any other Open Source Web Application. Highly configurable & modular, all the features are optional and administered via a web-based interface.
Major features include a robust wiki engine, articles, forums, newsletters, blogs, a file/image gallery, bug & issue tracker, a links directory, polls/surveys and quizzes, a FAQ, a banner management system, a calendar, maps, Mobile Tiki (PDA and WAP access), RSS feeds, a category system, a theme control center, a workflow engine, live support, Shoutbox, an advanced user, group and permission system and more.