The RLZ string isn't unique per user, and AFAIK it isn't used at all by Google's ad systems. It's used to measure the effectiveness of Google's marketing of the

The RLZ string isn't unique per user, and AFAIK it isn't used at all by Google's ad systems. It's used to measure the effectiveness of Google's marketing of their own software. http://code.google.com/p/rlz/wiki/HowToReadAnRlzString http://code.google.com/p/rlz/wiki/HowToReadAnRlzString