GRA4 Social Network for Drupal
GRA4 Social Network for Drupal is a free component, arming a website with full-blown social networking functionality.
After single 3-minute-long installation your website will have likes, groups, friends, blogs, messaging, documents, activity stream, market, events, and much more.
Big social networks put plenty of websites out of business, because anyone can create a group on a major Social Network (such as Facebook, VKontakte, LinkedIn, Odnoklassniki, etc.), and it's much easier than to build and support whole website.
We want to get web-masters back into the game, arming them with the same functionality the "grown-up" social networks have.