WebTools is "system" of multiple modules and libraries. Along with template engine capabilities, it features session management, global variables support, cookies support, and various database interfaces. It also features a pure Perl mail client, categories management, form checking, and libraries such as a CGI-based downloading library, HTML parsers, and a library that makes PHP functions available to Perl for ease of development.
SwenDeleter tries to identify email messages infected with the Swen worm in POP3 mailboxes and delete them on the server. It applies some heuristics to the headers and size of the messages, in order to avoid downloading the actual email, thus making retrievals less taxing. It has both interactive and nonstop modes.
SmartList is a mailing list manager. It is built on top of procmail and provides for the simple creation and handling of mailing lists, including fully automated subscription/unsubscription/help-request processing, intelligent auto-removal of addresses from the list that cause too many bounces, and a built in archive server (with MIME support).
Dkfilter is a DomainKeys implementation for the Postfix mail transfer agent. It is implemented as two filters (or SMTP proxies). There is an "outbound" filter for adding DomainKeys signatures to outgoing email and an "inbound" filter for verifying signatures of incoming email. The filters can be plugged into Postfix as either Before-Queue or After-Queue Postfix content filters. For more information about DomainKeys, see http://antispam.yahoo.com/domainkeys.
dkimproxy is an SMTP proxy that signs and/or verifies Domain Keys Identified Mail (DKIM). It is designed to work with Postfix. It comprises two separate proxies: an "outbound" proxy for signing outgoing email, and an "inbound" proxy for verifying signatures of incoming email. With Postfix, the proxies can operate as either Before-Queue or After-Queue content filters.