Chrome only -
https://chrome.google.com/webstore/detail/ejpepffjfmamnambagiibghpglaidiec
Facebook is notified whenever you visit one of the more than one million sites on the web that use Facebook Connect and has a history of leaking personally identifiable information to third parties.
Turn off the flow of your data to them!
Facebook Disconnect blocks all traffic from third-party sites to Facebook servers, but still lets you access Facebook itself.
https://chrome.google.com/webstore/detail/ejpepffjfmamnambagiibghpglaidiec