Ask HN: Is anyone working on a replacement for email?

Email’s defining characteristic is how it’s decentralized—no single company has control over the protocol. This has been both a blessing and a curse, and for better or worse, email is mostly stuck in the 80s with a little bit of HTML sprinkled in.

I hear Slack get thrown around a lot by people wanting to replace email with instant messaging, but it not only isn’t decentralized but also doesn’t serve many of the purposes (authentication, a universal identifier, etc) that email has come to serve.

Are you working on something to replace email? Are there any projects that are starting to replace email for you?