Background People have different identifiers, of different security, that they give out depending on how much they trust you. Examples might include: Homepage URL (very public) Email address (little bit more secret) Mobile phone number (perhaps pretty secretive) As has been shown with OpenID, XFN, etc... URLs are people too. You can do a lot of things with a URL: give out information, point to oth
![A proposal: email to URL mapping](https://cdn-ak-scissors.b.st-hatena.com/image/square/74e90599656ceadb00e4e45cf296cc44473e9e7e/height=288;version=1;width=512/https%3A%2F%2Fl-stat.livejournal.net%2Fimg%2Fsign.png)