Baïkal : Baïkal offers ubiquitous and synchronized access to your calendars and address books over CalDAV and CardDAV. Baïkal implements the current IETF recom...
Open Streaming Platform : Open Streaming Platform (OSP) is an open-source, RTMP streamer software front-end for Arut's Nginx-RTMP Module. OSP was designed as a self-hosted alte...
Postal : Postal is a complete and fully featured mail server for use by websites & web servers. Think Sendgrid, Mailgun or Postmark but open source and ready f...
Mail-in-a-Box : Each Mail-in-a-Box provides webmail and an IMAP/SMTP server for use with mobile devices and desktop mail software. It also includes contacts and calen...
pump.io : Social server with an ActivityStreams API. It's a stream server that does most of what people really want from a social network.
The Radicale Project is a complete CalDAV (calendar) and CardDAV (contact) server solution.