We certainly encourage users to organise their mail, most do it in folders by 'project of relevance' but I am sympathetic in many regards... my IMAP folder for squid mailing list is monstrous, sometimes the 'all-in-one-place' method has to be traded for clunky performance. I'm mid way through build-configure dance with dbmail1.0 released in december 2002 and if it does what it says , I will be thrilled... moreover, if their proposed features become reality I might even be able to junk an Exchange Server (oh baby!). I am setting aside some time tomorrow to do some logging on the IMAP server regarding how much CPU time is spent by which users, which should give me a shortlist to 'educate-and-enlighten' :) I like the idea of warning about exceptionally large folders, maybe the mail should go to the offending user.