Mailcrypt is an Emacs Lisp package which provides a simple interface
to public key cryptography with PGP. Mailcrypt makes strong
cryptography a fully integrated part of your normal mail and news
handling environment, and is an important part of a balanced
breakfast.

Features :

 *  An interface to the usual PGP functions, including encryption,
    decryption, signature creation, signature verification, key
    addition, and key extraction 
 *  A passphrase cache with configurable timeout 
 *  Support for multiple secret keys 
 *  A flexible interface to anonymous remailers, including Mixmaster
    support 
 *  An automagic interface to the PGP public key servers through HTTP 

http://cag-www.lcs.mit.edu/mailcrypt/

- Murray Stokely
murray@cdrom.com