filter out everything except people with whom you want to exchange mail.

If you would like to add some more features to your procmail service, read the procmailrc manual page. For a great selection of procmail recipes, see the procmailex manual page, which details numerous examples, ranging from the simple to the complex.

Want more information about procmail, writing procmail recipes, and filtering your mail? Look for Nancy McGough's Filtering Mail FAQ, which is posted regularly to the comp.mail.misc, comp.mail.elm, comp.mail.pine, and other newsgroups. Reading news from Usenet also happens to be the next hour's subject!