When I moved from OpenBSD to FreeBSD a year ago, I also had to move the email being handled by my server. As things were a bit different, I added a "Just-in-case" MailDir for one of my users so that no matter what else happened to the rest of their procmailrc, they'd have a backup copy.
Flash forward a year.
Yeah, you guessed it... we never turned that off. It's been accumulating spam at the rate of a few messages a second. For a year. I couldn't figure out why my 80GB of freespace a year ago was now dangerously under 15GB.
The MailDir/new directory was 2.5GB. Not t…