Lovd offers a free open source social network platform. Built with Ruby on Rails, Lovd is a social networking solution that has everything you need to build your community.
Features:
> Follow a user, mutual following is friending.
> User-to-User Messaging
> Profile Comments
> User Blogs with Comments
> Photo Gallery with Captions
> Site Search for Friends
> Profile Bio and Information
> User Dashboard
> Emailed Activity
> Flickr Integration
> YouTube Integration
