A fast, highly extensible, and event driven SMTP server
Haraka is a highly scalable node.js email server with a modular plugin architecture. Haraka can serve thousands of concurrent connections and deliver thousands of messages per second. Haraka and plugins are written in asynchronous JS and are very fast. Haraka has very good spam protection (see plugins) and works well as a filtering MTA. It also works well as a MSA running on port 587 with auth and dkim_sign plugins enabled.
Untangle is a Linux-based network gateway with pluggable modules for network applications like spam blocking, web filtering, anti-virus, anti-spyware, intrusion prevention, bandwidth control, captive portal, VPN, firewall, and more. Visit http://untangle.com
javascript to convert thunderbird/seamonkey filters to sieve rules
Web form that converts pasted rule set from thunderbird/seamonkey msgFilterRules.dat filter file into sieve rules suitable for uploading to an imap mail server and compatible with the sieve rule editor plugin for roundcube 'sieverules' (http://www.roundcubeforum.net/7-third-party-contributions/46-api-based-plugins/4878-sieverules-plugin.html)
mx-LDAP-Suite
mx-LDAP-vacation: auto responses mail on vacation and reads the message from LDAP.
mx-LDAP-admin:Is a PHP based tool. It provides administration of LDAP-Directories
(Add, modify and delete user-accounts,groups,aliases,
samba-workstat