HybridAuth, Open Source Social-Signle-Sign-On Solution for authentication through Facebook, Twitter, Google, Yahoo, MySpace, LinkedIn, AOL, Vimeo, FourSquare, OpenID and other Identity providers
►http://hybridauth.sourceforge.net
HybridAuth is an open source web-based authentication and authorisation solution that combines the strengths of several major social networks and Identity Providers services into one simple PHP Library.
via @b_b