Open Source JavaScript Email Spam Filter Software for Mac

Spamato is a spam filter system that combines several anti-spam techniques, from which thousands of users benefit. It is available as an add-on for Thunderbird and Outlook, and as a stand-alone proxy for other email clients. IMAP and POP are supported.

ThunderRetract implements client-side eMail retraction into Thunderbird. This is done showing messages differences in original and retracted one. Support: thunderretract@gmail.com

A Mozilla Thunderbird Add-on for managing remote sieve scripts. It's a JavaScript based implementation of the ManageSieve Protocol (RFC 5804).

Bunch of useful filters for AngularJS (with no external dependencies!). You can install angular-filter using 4 different methods. Include angular-filter.js (or angular-filter.min.js) in your index.html, after including Angular itself. Add 'angular.filter' to your main module's list of dependencies. If a string is provided, it will filter out duplicates using the provided expression.

Attachment Reminder is an Add-On (extension) for Mozilla Thunderbird that scans outgoing email for user-defined keywords (or just use the default list), and prompts you if it looks like you wanted to attach a file but didn't.

FilterBadRecruiters is a Google Apps Script that processes new messages looking for unwanted email from known third party recruiters. When a match is found, a reply is sent informing the sender that the message is being reported as spam and will not be read. The script then logs matches to a spreadsheet and updates a pie chart displaying what percentage of these type of messages were sent from each domain.

Web form that converts pasted rule set from thunderbird/seamonkey msgFilterRules.dat filter file into sieve rules suitable for uploading to an imap mail server and compatible with the sieve rule editor plugin for roundcube 'sieverules' (http://www.roundcubeforum.net/7-third-party-contributions/46-api-based-plugins/4878-sieverules-plugin.html)

NOTICE: Keep in mind that POP3ye is alpha software and by definition it is a long way from finished. POP3ye is a fully featured web-based e-mail client written in Object Oriented PHP 5. It ony supports the POP3 protocol.