Artica for Postfix is a secure Web interface for Postfix administration. It is designed to reduce the cost of creating and managing a full Linux mail server. It supports Postfix, Kaspersky Anti-spam, Kaspersky Anti-Virus, Bogofilter, Milter-greylist, SpamAssassin, Clam Antivirus, Amavis, OpenLDAP, SQLite library, Cyrus-imap, Procmail, Fetchmail, DnsMasq, Mailman, Sieve, Yorel script, QueueGraph, MailGraph, AWSTats, geoip, and more.
xtee (cross-tee/expanded tee) is a program for building complex pipelines. It resembles the tee command, except that instead of copying stdin to stdout, it copies an input file to stdout and stdin to an output file. You can use xtee for building things like a bidirectional HTTP filter (using netcat and sed).
DynaStop is a utility to examine IPv4 based addresses for Exim and procmail for the purpose of filtering based upon patterns defined by the administrator. This can be a pivotal factor in email filtering and server load management, since dynamic IP addresses are typically used for dial-up, DHCP, and DSL accounts. All of which have a designated mail exchange server through which all outbound mail flows as defined with many, if not most, large Internet service providers.
The QmailToaster is an RPM-based Qmail distribution for CentOS, Fedora, SuSE, and Mandriva. This system is designed for ease of deployment and includes strong anti-spam systems. This includes support for SRS, SPF, DomainKeys, and virtual hosting on the SMTP side. On the user side, this has a Web-based administration interface and supports POP3, POP3 over SSL, IMAP, and IMAP over SSL.