Visualize who's tracking you in real time. To get started, click on the Collusion icon in the bottom-right corner of your browser. (You may need to show the Add-on Bar to see the icon.)
Collusion is an experimental add-on for Firefox and allows you, for the first time, to see all the third parties that are tracking your movements across the Web. It will show, in real time, how that data creates a spider-web of interaction between companies and other trackers.