Ever post something to facebook (what, you have a facebook account??) & immediately (or a bit later) regretted it? A Qualitative Study of Regrets on Facebook – This must be the most entertaining research paper ever written! (pdf download).
..little is known about the problematic aspects of Facebook usage. Our research fills that gap by showing that regrettable postings are not unusual. We devised a detailed taxonomy of regrets and discovered that they are mainly centered around sensitive topics, emotional content, and unintended audience. Furthermore, our results agree with many news stories that report that regrettable postings on Facebook can yield serious ramifications for users.