GPGMail A plug-in for Apple’s Mail (on MacOS X) and MailViewer.app (on old MacOS X Server 1.x), providing a front-end to gpg for some operations. GPGMail extends Apple’s Mail/MailViewer application and allows you to read and send PGP authenticated and/or encrypted messages. You can use PGP for plain and MIME messages, following RFC 3156. Source code is available. Developed and maintained by Stéphane Corthésy of Sen:te.