I am tired of the existing Internet email system, both as a sender of email, as a recipient, and as an operator of an email server.

I've been thinking about ways to solve that, and have written an essay about it, without any plans to work on implementing a solution. I'm interested in inspiring more discussion. See HTML and PDF versions. It's a bit long, and does not yet address more than the spam problem.

TL;DR: I don't think the current email system can be improved enough to be worthwhile, but a new system could use digital signatures and digital stamps (tokens) to only allow recipients accept mail from specific senders.