"Any other's you're interested in?"

mutt?

We send a multi-part message so that text-only clients get a plain text mailer as well as HTML.

Thank you for doing this. I laugh whenever I open the plaintext version of an email and it still has the default text of "Insert a text version of your message here for users without images to read"!

It's actually one of our cofounders who wrote this, not me, but I'll pass that along. :)