proton mail

MailFX is a notifier which replaces (or complete) the sound warning of Mail OSX.

Export new Mail.app message to iCal calendars.

Export Mail.app message to iCal ToDo list.

Add cards in Address Book from selected Mail messages.

A plugin for Apple Mail that shows messages

IMAPCheck is a bundle for Mail.app

Plugin for Mail.app takes advantage of widescreen monitor.

A new open-source mail client for Mac OS X.

Block access to incoming and/or outgoing mail servers and websites

Assists administrators backing up mail settings and stores.