Revue is an email newsletter service run through your Twitter profile, with the option of charging to receive your newsletters. Twitter keeps 5% of the revenue, and you get the rest. You can import an audience list, and keep your audience list when you leave.
It is also helpful for Revue to be directly on Twitter, as when you subscribe the platform already knows your email address so you don’t need to fill in any forms (just click a button). This will increase subscribe rates by removing friction. It should be noted that you can change the email address you want to subscribe with if you like.
You can also read a sample issue of the newsletter before you commit to it, which is a really great feature.