Mailo - Mailo is an email client where you can send and receive emails to and from anyone with an email address.
Postfix - Postfix is a mail transfer agent (MTA) that routes and delivers electronic mail.
HEY - Email at its best, new from Basecamp.
sSMTP - sSMTP is a simple MTA to deliver mail from a computer to a mail server.
Horde - Horde Groupware is a free, enterprise ready, browser based collaboration suite.
OpenSMTPD - OpenSMTPD is a FREE implementation of the server-side SMTP protocol as defined by RFC 5321, with...