If someone can figure it out I'd love to see it. Having some way of preventing someone from making more than one account would be a tremendous help in my eyes. Whether you use your name or not, that account is you. If it gets removed, you're off the site.
What I can't figure out is how you would do this while staying anonymous. If the users had some private key they could sign the account in some way to claim ownership without saying who they are, but then who issues and maintains the private keys? You'd need some large body to issue them, and that means storing personal data to know who has and hasn't been issued a key.
What I can't figure out is how you would do this while staying anonymous. If the users had some private key they could sign the account in some way to claim ownership without saying who they are, but then who issues and maintains the private keys? You'd need some large body to issue them, and that means storing personal data to know who has and hasn't been issued a key.