Discussion List Plugin?

Hello,

I hope someone can help me or point me in the right direction. I’m looking at creating an email discussion list with subscribers to my WordPress.org blog.

It doesn’t have to be tied with a blog post, although it could — or, preferably, an initiating email could be a blog post (such as mo blogging). But the most important thing is to allows registered users of my blog to email a group list, which echoes the email to the rest of the subscribers (the blog is a private one, just so you know).

Thanks.