Pligg - Social Publishing CMS

Pligg is an open source CMS (Content Management System) which provides social publishing software that encourages visitors to register on your website so that they can submit content and connect with other users. Our software creates websites where stories are created and voted on by members, not website editors. It is a user driven CMS that relies on independent authors content and participation to manage news articles.

It has support for Groups, Private messaging, User profile management, SEO support, RSS feeds and lot more. It is a CMS with social publishing feature.