Anti-Spam SMTP Proxy Server implements multiple spam filters
Google Apps Script to send third party recruiter email to spam
The free cross-platform antivirus software tool-kit
Converts quoted-printable, UTF-8, UTF-16BE, UTF16LE to 8-bit.
Tools to convert Z mark-up to HTML or text.
Obsolete SARE rule archive - SpamAssassin autogenerated rules
Source code for be able to use Relation Tags.
javascript to convert thunderbird/seamonkey filters to sieve rules
A PHP sieve library
email based anonymous voting program