mbox cleaning

Sometimes, for various reasons (e.g. POP3 accidents), you might end up with a mailbox full of duplicate messages. To remove the extras, you can use a handy procmail utility named formail as follows :

formail -D 10000 idcache -s < mboxwithdupes > mboxclean

You can adjust the 10000 number to limit the number of unique Message IDs stored in...