Is there an add-in for Microsoft Outlook that will assist in filing emails in folders by guessing the folder that an email should go in? The software on my blackberry does this, guessing with great accuracy, I assume based on some text analysis of the sender and the subject line. It would be helpful to have the same functionality in Outlook.
My favorite is SimplyFile
How about Outclass?
I searched for something that uses Bayesian filtering to sort into N buckets instead of just two buckets: Spam/Ham (non-spam). The Bayesian algorithm requires some training at first, but it seems to be very accurate (over 99.X%). This accuracy may go down as you add more buckets (I'm not sure)...
This discussion from The Joel on Software Discussion Group led me to Outclass. I haven't used it myself, and it seems to only support POP (no IMAP)