Training SpamAssassin with a LearnAsSpam IMAP folder

I’ve found that many installations of SpamAssassin work well, but end-users don’t optimize them to train their Bayesian filters on false negatives (i.e., spams that get through). A LearnAsSpam IMAP folder is a great solution for this, which even works with Exchange users (they just need IMAP turned on at the server).

I wrote up directions for installing this on the SpamAssassin wiki.