A great talk by Jake Appelbaum that one should watch: https://www.youtube.com/watch?v=6kilAPZ-vGA A very in depth and revealing talk about the current state of the union of 'identity' on the web and the apparent digital doppelgängers we carry around with us. Frankly the notion of a digital doppelgänger is hillarious and identity is not a hard problem when people are effectively schizoid when they surf and flitter between multiple idens all the time.