Roap is a text file processor. It scans a text file, extracts regions that match specified patterns, and processes these regions sequentially using specifed executables. Each executable reads the region as stdin, and their combined stdouts are written as the stdout of Roap. Patterns and executables are specified using XML.
mailagent uses lex-like rules to match messages and run rich set of commands. Mail can be stored in mailboxes, forwarded, piped through external applications, posted to newsgroups, checked for duplicates, annotated, or deleted. Headers can be pruned and digests burst. Additional commands can be written in Perl.
OdeiaVir intercepts email messages about to go into a user's mailbox (qmail or Exim mail servers are supported) and scans them for viruses. The supported AV packages are ClamAV, AVG, McAfee VirusScan, F-Prot, Panda, Sophos Sweep, CA InoculateIT, F-Secure, BitDefender, and the OpenAntivirus ScannerDaemon.
Active Spam Killer (ASK) protects your email account against spam by confirming the sender's email address before actual delivery takes place. The confirmation happens by means of a "confirmation message" that is automatically sent to all "unknown" users. Once the sender replies to that message (a simple reply will do), future emails from that person will be delivered immediately. You can also specify (regexp) addresses to be immediately accepted, rejected (with a nastygram) or ignored. The package also includes a utility to scan your old mailboxes and generate a list of emails to be accepted automatically.
Originally based off the program qmail-masq, qmail-masq-user uses qmail and qmail-qfilter to change the From: address of outgoing emails to almost any combination of username, domain, or both. The configuration allows you to specify domain catch-alls, user catch-alls, email catch-alls, specific combinations of users and/or domains, and much more.
ScannerDaemon is the virus scanner of the OpenAntivirus project. You can send a filename to it via simple TCP and it will scan the file for viruses and tell you if the file is infected or not. The ScannerDaemon comes with its own virus database, so you do not need any commercial virus scanner. There is a plugin for AMaViS and several mailservers to scan all EMail going through a mail server.