phlyMail is a groupware, webmailer, and PIM. It offers unlimited nested groups, unlimited POP3/IMAP profiles, quotas, an integrated address book, a calendar with multiple reminders and event repetitions, a file manager with an integrated WebDAV server, the ability to send faxes, SMS support (which lets you send SMS, get reminded of events via SMS, and get email notification via SMS), a bookmark manager, themes, and multilingual support. It uses either sendmail or SMTP to send email, and can handle MIME and SSL connections. Support for IDN (Internationalized Domain Names) is included. Through its modular design, it's easy to add completely new features as modules, which can be plugged into the system.
ADJE WebMail is a set of Perl CGI scripts which provide a Web interface to existing email accounts on any POP3-compliant email server. The software provides a complete interface, including encoding/decoding attachments, email and URL markup in received emails, and an address book for each user.
Elm Millennium Edition is a text-based mail client. There are two branches: Elm 2.4ME+, which is based on Elm 2.4, and Elm ME+ 2.5, which also incorporates some code from Elm 2.5. Elm Millennium Edition contains enhanced MIME and character set support. A subset of UTF-8 (Unicode) is handled. It can read mail from a local mbox and POP and IMAP folders and can pass mail to the PGP or GPG programs. It can also view digests as a mailbox and reassemble fragmented (message/partial) messages. It includes modules for TLS/SSL, iconv, and SMTP.
The Courier IMAP/POP3 maildir creation patch adds the ability to automatically create a user's home directory when he/she is successfully authenticated for the first time. It works by calling an admin-created script that takes care of creating the directory. It is quite useful in combination with authentication-modules based on network databases like MySQL or LDAP.
Elmtree Express Server is a realistic alternative to the Microsoft Windows server plaftorm. Express Server is a workgroup server solution, providing your business with integrated email, print management, and data storage functionality, all in one easy package. It includes an email server, a central address book via LDAP server, a DHCP server, a central file server, a print server, automated daily backups, GUI administration tools, and more.