[web-devel] Sending email

Hey all, I'm wondering what people do in general for sending email, especially from web apps. So far, I've written some basic modules in my apps that wrap around the sendmail executable on the system. Are there packages on Hackage that people would recommend? As long as I'm bringing this up, I think I nice email system would offer built in support for creating multipart messages. Bonus points would be to automatically create a text/plain version from an HTML version. If no one knows of prior art on this, I might try to implement it as a module in Yesod. Michael