Mr Mad Monk (or Rev or Father or whatever),
The mail application that comes with OS X has a very good junk mail filter. I gave up on Entourage last week - claims to have filters, but nowt seemed to work.
The Apple one worked almost perfectly after only one day of 'training'.
This evening I got four real messages and 72 piles of poo. All correctly identified.
I'll have a look at POP monitor and see if it's even better.
Spam, spam, spam, spam, lovely spam, wonderful spam.