I wrote a simple script ages ago to take care of those pesky bounce messages
w/o any homes... I'm sure there's a better way to do it, but I usually go the
simple, complex route. ;-) I put this in my daily crontab.
I also wrote one to fix the permissions on all my files/folders since
linuxconf, mandrake's security program, and a few others kept changing the
permissions every night.