I think that anonymity is impossible; you could assign a unique number to each individual in something like 33 or 34 bits, which means you could de-anonymize yo

I think that anonymity is impossible; you could assign a unique number to each individual in something like 33 or 34 bits, which means you could de-anonymize your pseudonym in as few as 33 or 34 bisecting pieces of PII. (Gender identification provides at least one bit, and possibly more for someone who is homosexual; specifying a geographical region provides a few more.) It's a nice ideal, but I think being anonymous is going to die in the next five years -- if it hasn't already.