Email doesn't require DNS. Modern spam solutions for DNS do. You can most definitely use something like `spiped` to create a mutually authenticated, secure chan

Email doesn't require DNS. Modern spam solutions for DNS do. You can most definitely use something like `spiped` to create a mutually authenticated, secure channel over IP, and just send mail over that. Or build a VPN overlay network and send mail to raw IPs. If you're going to cloister yourself with your fellow monks^W nerds then this is simple.