I've always had the need to quickly just setup an email service for all the different projects and communities that I run, so I built KaiMail to do that. I can't stand the fact that getting emails for your domains can be so difficult compared to setting up a static website.
If you're running an open-source project or an open-source community, I'm happy to get you an upgrade at no cost.
Show HN: Custom domain emails for open source projects (KaiMail)
kaimail.net