Comcast is tracking you
Wouldn't it be nice if every time you visited a website, big brother was there to check out what you were doing on that website and nagging you on your computer screen to go get a better job so you can buy more shit you don't want/need? Well, Comcast just took the first steps toward that reality. They're hijacking people's internet connections and injecting what I would call malicious code into them. The purpose of the code is to be able to notify you of whatever information they seem to think is useful at the moment. One can only assume they're also logging your website visits in order to sell your information to advertisers. Check out this link for a nice writeup: http://blog.ryankearney.com/2013/01/comcast-caught-intercepting-and-altering-your-web-traffic/
And here for the gist of the code: https://gist.github.com/ryankearney/4146814