Lightbeam for Firefox
At Mozilla, we believe that everyone should be in control of their user data and privacy controls and we want to help you make informed decisions about your Web experience. With this in mind, we've developed Lightbeam, an add-on for Firefox that will help users visualize the array of companies they're interacting with every day on the Web.
More about Lightbeam for Firefox: http://mzl.la/1g0k5Qq.