I installed the Collusion plug-in for Firefix that graphically depicts all the third party sites that track you as you browse the web. I then visited the following sites: Drudge Report, The Daily Caller, ESPN, Politico and Macworld—5 sites in my “Daily Reads” folder that I visit…umm, pretty much daily. And this is what collusion showed after about two minutes:

Five of those circles are the result of me selecting a site to visit. The rest are not. Frightening.