Hastymail is a fast, secure, rfc-compliant, cross-platform IMAP/SMTP client application written in PHP providing a clean web interface for sending and reading E-mail.
This version of Hastymail is no longer being developed. We are now working on a new version, Hastymail 3, AKA, "Cypht".
http://cypht.org
NEXUSe2e client is an Eclipse RCP application that provides XML based messaging using e.g. ebXML to integrate business processes that span multiple companies. It enables small organizations to participate in supply chain integration scenarios.
hMailServer is a SMTP/POP3/IMAP server for Windows. Data is stored in MySQL/MSSQL database and is easily accessed using the COM library. Project info, trackers and downloads has moved to www.hmailserver.com.
Tortoise Mail is a POP3 and SMTP E-Mail Client written in PHP. By using PEAR Package DB, it supports many SQL-Based Databases (dbase, fbsql, ibase, ifx, msql, mssql, mysql, oci8, odbc, pgsql, sqlite, sybase). It is also PHP 5.x compatible.
IMAP4 server working on top of SQL database (currently PostgreSQL but Oracle may work too). It has some unique features like elimination of duplicate messages throughout the whole system, possibility of clustering or load balancing etc.