Skybrud.Social (http://social.skybrud.dk/) is a standalone framework in .NET that I released in the spring of 2013. The framework helps developers in making an easy integration with services like Facebook, Twitter and Instagram.
On top of that framework is now this package - Skybrud.Social for Umbraco - which I showed briefly in the Package Competition at Codegarden '13. The package utilizes the features of the Skybrud.Social framework and gives developers a set of data types for handling the OAuth authentication from Umbraco - currently for the services Facebook and Instagram.
You can find documentation of Skybrud.Social at: http://social.skybrud.dk/umbraco-package/