Keybase
Keybase is working hard to bring all the promise of public key cryptography to regular people. We're solving three challenging problems in parallel, building out: (1) an open and auditable PKI based on social network identities; (2) support for all mobile and desktop platforms, so that every device can have its own private key; and (3) viral sharing applications that use clean UX to hide the complexity we've all come to associate with public keys. We want to change the way security works at a deep level, so that sharing, end-to-end security, and cloud hosting can peacefully coexist. And we won't be happy with isolated enterprise installs, or appeal to just hardcore tin-foil hats. We're aiming for widespread adoption: first among programmers, and eventually among consumers at large.