tkbiff allows arbitrary commands to be executed upon mail reception. If you like programs such as xbiff and xbiff++ but wish they were more flexible, then you'll like tkbiff. Unlike other biffs, tkbiff is fully customizable. tkbiff also doesn't waste your valuable screen space with icons; instead, it shows you the mail itself. It supports UNIX, Mac, and Windows, IMAP, POP, and UNIX-style mail files, and SSL and APOP.
yaspi (Yosi's Anti-Spam POP3 fIlter bot) is a POP3 mail-scanner specifically made to combat mail bombings caused by viruses (i.e. Swen). It connects to the POP3 server, inspects the messages, and deletes the infected ones without ever downloading them. Its most interesting feature is that it can automatically send abuse reports to the ISPs from which the infected mails originated.
Zoho Virtual Office provides a virtual collaboration platform with which individuals and groups can communicate, collaborate, organize, and share information seamlessly. The collaboration suite includes email, documents, calendar, tasks, contacts, notes, links, IM, and more. Zoho Virtual Office allows users to create multiple groups and provides smooth collaboration of these components within groups. All data in the system can be accessed from any computer that has an Internet connection and a Web browser.
getmail is intended as a simple, secure, and reliable replacement for fetchmail. It retrieves email (either all messages, or only unread messages) from one or more POP3, SPDS, or IMAP4 servers (with or without SSL) for one or more email accounts, and reliably delivers into qmail-style Maildirs, mboxrd files, or through external MDAs (command deliveries) specified on a per-account basis. getmail also has excellent support for domain (multidrop) mailboxes, including delivering messages to different users or destinations based on the envelope recipient address.
mpop is a small, fast, and portable POP3 client. Its features include header-based email filtering (filter junk mail before downloading it), delivery to mbox files, maildir folders, or a mail delivery agent, a very fast POP3 implementation, many authentication methods, and good support for TLS/SSL.
Collaba is a multimedia collaboration and communication server built to provide digital workspaces to virtual educational, corporate, and other communities. It features secure email (Web, POP3/SMTP, crypto, and anti-spam), online forums (Web, RSS, NNTP, and podcast), blogs (Web, RSS, podcast), multimedia chat (text, multimedia panel, etc.), personal and group calendering, address books, bookmarks, an online Web page editor, file services and CMS (Web, WebDAV, FTP, SMB, CIFS, anvi-virus API, and ClamAV support), digital portfolio, dynamic news board, directory access, support for multiple independent communities on one server, Single-Sign-On features (built-in support for LDAP, CAS 2.0, JAAS, SMTP-Auth and more, powerful developer API), full online server management, anti-spam (RBL and filters), anti-virus support, centralized management with LDAP directories, Web publishing of personal, group or general web sites, developer APIs, and much more.
Roundup is an issue-tracking system that is simple to use and simple to install. It has command-line, Web, and email interfaces. It manages a number of issues (with flexible properties such as "description", "priority", and so on) and provides the ability to submit new issues, find and edit existing issues, and discuss issues with other participants. The system facilitates communication among the participants by managing discussions and notifying interested parties when issues are edited.