If you’ve logged in to a Stack Exchange site recently you may have noticed a new button on the login page:
That’s right — Stack Exchange is now officially an OpenID provider as well as an OpenID (and OAuth 2.0) consumer!
As a provider, we can now provide a totally seamless signup experience for new users. That is, you can create a new account entirely on our site without ever once being redirected to another website in the process.
Those users who were uncomfortable with Google, Facebook, MyOpenID, AOL, or any other form of OpenID credentials can now create “local” accounts. …