SMTP email proxy and relay server
A simple and fast cross-platform solution to send mass emails.
Python API for Sendmail Milters.
Full SMTP/Mail server Appliance in 5 minutes
An unofficial web console to administer Apache James 3 server
Simple web interface for Postfix domains, accounts, aliases
Ciphermail email encryption gateway (S/MIME, OpenPGP, PDF encryption)
PHP powerful tool for sending e-mails fast and easily