Do you love Facebook, G+ and similar sites? The social network is a big trend.
There are free web solutions that allows you to create your own social network.
What are the benefits of a social network?
Social networks offers unlimited possibilities: from creation of customized community of friends/fans, promotion of a product/service and the users create the content!
Many solutions are based on popular CMS like Joomla, Drupal, WordPress etc… so lets show:
Buddypress an addon that transforms the popular WordPress CMS within specific plugins in a social network with profiles, forums, individual blogs, groups and much more
Elgg very popular from opensource social systems, stability, features and friendly community
Community Builder for Joomla, has many extensions and lot of features: extra fields in profiles, users list, images upload, integration with other components, etc…
Drigg Drupal module, Digg clone
Pligg CMS opensource social network oriented and PHP and MySQL based, modules support