Liferay
http://www.liferay.com/
Liferay Portal is the world's leading open-source portal for the enterprise. Its built in web content management system (Liferay WCM) comes with extensive web, portal and workspace publishing features. Liferay WCM also leverages Liferay Portal's system of role-based authorizations, single sign-on, web services support, theming, dynamic navigation and dynamic social collaboration functionality.
Liferay sites showcase, 1580 sites using Liferay
