Several of my friends use pseudonyms on Facebook, although ones that are usually recognisable as manglings of their real names ("John A Smith" -> "Jonas Mith",

Several of my friends use pseudonyms on Facebook, although ones that are usually recognisable as manglings of their real names ("John A Smith" -> "Jonas Mith", say). In their cases, I believe the main intent is to stop prospective employers finding their drunken-student-party photos, but I guess it might contribute to privacy in other small ways too.