SaltOS, ERP, CRM, Business Management Suite, Josep Sanz Campderrós
Fast Bayesian spam filter along lines suggested by Paul Graham
Simple-to-use/-install issue-tracking system: web, REST, email, CLI
Strong Email & Apache Log Analysis with Active Security Features
Short perl script mail delivery agent
Multi-protocol server written in Java
An easy-to-use anti-spam email gateway
imap cleanup & command line tool
Conversion from *.mht files to *.htm files.
Ciphermail email encryption gateway (S/MIME, OpenPGP, PDF encryption)
Python + espeak gmail checker
Advanced Spamming Tool
A free .NET library for accessing IMAP servers, written in C#
Conversation manager