Regarding the “de-anonymizing” the web, two years ago in Paris, I met a mathematician working on pattern detection models. He focused on locating individuals simply through their cell phones habits. Even if the person buys a cell phone with a fake ID and uses it with great care, based on past behavior, his/her real ID will be recovered in a matter of weeks. (As for Facebook, it recently launched a snitching program aimed at getting rid of pseudonyms — cool.)
Click through to mondaynote.com and read the entire post. Very interesting thought piece and probably not far off the mark.