MailStripper Pro is a mail scanner that aims to remove spam and viruses from incoming mail. It recognises and decodes many obfuscation techniques used by spammers and uses several different mechanisms to recognise spam which are immune to Bayes poisoning, and has achieved real-world success of over 99.8%. It is MTA-independent and does not implant itself into your mail server. Instead, it functions as a proxy, allowing the MTA to reside on a different server.
TkRat is a graphical Mail User Agent (MUA) which handles MIME. It is mainly written in C, but the user interface is done in Tcl/Tk. The program currently understands UNIX mailboxes, POP, IMAP, and mh folders. Messages are sent via SMTP or any user configured program (sendmail, for example). It has support for disconnected IMAP operations.
The BID software was designed to apply business rules to your email traffic. Business information can come from business applications, monitoring applications, or normal users requesting or providing data. The goal of the BID tool is to automate the dispatching of this information and to join a business-case with a responsible receiver. A receiver can be a human being or another BID server customized for a special business-case. The BID server was designed as a generic server using plugins to serve specific business-rules.
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.
sendPGPMail.cgi is a small CGI script for sending an encrypted PGP email message to a predefined receiver from an HTTPS secured Web page. The typical use of this script is to provide the users of a secure Web site the possibility to send a secure email to a predefined employee of a company. The CGI script gets its input from an HTML form and passes it on to gpg. The message and its attachments are encrypted using the PGP public key of the predefined receiver.