Kliqqi

Kliqqi formerly known as Pligg CMS is an individualized content management system that lets you to easily create a social network or online social community similar to Facebook, Reddit, or Twitter,  where users can publish articles, vote on them,  leave comments, and share them with friends & family. The users are in control of the content. While most content management systems are designed for only one or two authors, Kliqqi was designed as a way for a large number of contributors to submit and moderate content.