GNU Anubis is an SMTP message submission daemon. It represents an intermediate layer between the mail user agent (MUA) and mail transport agent (MTA), receiving messages from the MUA, applying to them a set of predefined changes, and finally inserting modified messages into an MTA routing network. The set of changes applied to a message is configurable on a system-wide and per-user basis. The built-in configuration language used for defining sets of changes allows for considerable flexibility and is easily extensible.
Pico is a fast, full featured mobile application for any Java (J2ME) or Symbian cellphone. Including full HTML Web browsing, feature-rich email, multimedia-enabled SMS, and an RSS feed reader, Pico combines all the rich functionality of PicoWeb, PicoMail, PicoSMS, and PicoRSS into a single application.
Sendooway is a multi-user and multi-target ESMTP proxy that acts as mail transfer agent. Instead of configuring SMTP servers and authentication data for every mail identity on every device, it allows you to configure them centrally. Sendooway automatically uses the correct smarthost, logs on with the user's account data, and sends their mail.