Auth0 is the social login system we use. We wanted to make it easy, simple, and secure to login, and for people to not to have to re-enter information. Currently, you may see "Auth0 Sandbox" or a similar message when you are logging in.
Auth0 is an in-kind sponsor. Any startups that would like a discounted account, contact us.
Why only social logins?
We also decided to only allow logins with a social account. We currently support Twitter, Facebook, Google, and LinkedIn accounts. Auth0's list of supported identity providers are here »
By only supporting social logins, this means we are not storing a password. Since we don't have a username / password database, it can't be hacked. We think that the big guys do a better job of securing your information, and many of them also support multi-factor authentication so it can be as secure as you want.