Use procmail to automatically extract PGP keys from incoming mail messages.

Discusses positive uses.

A general introduction to mail filtering on Unix, with information about Procmail, filter, and mailfilter. (Slightly old and apparently no longer maintained, but still an excellent introduction.)

Procmail description and links to procmail program, documentation, and discussion groups.

This article will quickly get you up and running with Procmail. By Nancy McGough, of Filtering FAQ fame. (Contents are partially the same as in the Filtering Mail FAQ, too.)

A procmail-based filter system for bulk, unsolicited e-mail.

Contains the mailagent package itself. This is a Unix mail filter (a la filter, vacation, or procmail) written in Perl. Last updated sometime in 1997 ...

Official distribution site for Procmail.

Instructions for installing and configuring procmail and PGP for mail encryption and decryption..

Contains the FAQ, a links collection, and Quickref