Elgg
From DreamHost
Elgg is a white label, open source social networking platform. It offers blog, networking, community, collecting of news using feeds aggregation and file sharing features. Everything can be shared among users with access controls and everything can be cataloged by tags as well.
Installation
Elgg is not available via the DreamHost "one-click" installer, but can easily be installed on DreamHost servers using the default DreamHost PHP 5 PHP-CGI configuration and the documentation available at the elgg.org website.
