I configured mutt to automatically delete messages from mailing lists that are older than 21 days, provided that the message is not flagged or addressed to me. Here's what I came up with, in case it's useful to anyone else:
my_hdr From: Philip Mak <[EMAIL PROTECTED]> # alternate e-mail addresses set alternates=pmak@animeglobe\.com|pmak@animelyrics\.com|pmak@trapezoid\.interserver\.net set score # set scoring on score ~A 5000 # default score is 5000 set score_threshold_delete=0 # Delete messages with score = 0 score ~F +1000 # Increase score of flagged messages score ~p +1000 # Increase score of messages addressed directly to me # Decrease score of messages from mailing lists older than 21 days score "~e [EMAIL PROTECTED] ~r >21d" -5000 score "~e [EMAIL PROTECTED] ~r >21d" -5000 score "~e [EMAIL PROTECTED] ~r >21d" -5000 score "~e [EMAIL PROTECTED] ~r >21d" -5000 score "~C vim@vim\.org ~r >21d" -5000 score "~C mysql@lists\.mysql\.com ~r >21d" -5000 score "~C online-ads@o-a\.com ~r >21d" -5000
