Listening to alltechconsiderd on NPR this AM, they had a good discussion on how much private industry knows about you. It was pretty much what most of the techno savvy already knew, but still creepy to see how far the industry has come in predicting individual behavior.
"New Anonymous Facebook Login Hides Info, But Not From Facebook"
http://www.npr.org/blogs/alltechconsidered/2014/05/02/309025986/new-anonymous-facebook-login-hides-info-but-not-from-facebook