Ok, I got so frustrated by the lack of options on IMF (regardless of the XML custom weighting feature etc) that I decided to make a program that I'm sure more than enough people will appreciate.
I have only just started to program it today but it should work. What this program allows you to do is whitelist external (senders!) email addresses and also absolute delete emails that contain specific words.
There has been a patch by MS that allows you to whitelist recipients addresses but only pay-for IMF addons have previously allowed you to white list external (senders) addresses.
I will be testing it more over the next few days and making it nicer to use however it *should* work fine. The only prerequisites that I know it should require is .NET framework 2.0.
PLEASE REMEMBER TO SET DIRECTORIES IN Options->Configure Directories THE FIRST TIME YOU LOAD THE PROGRAM ELSE THE PROGRAM WILL FAIL TO WORK CORRECTLY.
Download here (14KB!)