I love SpamBayes. I've got it running in Outlook at work to handle the 150+ spams I get daily. My only problem with it is that it seems to interfere with regular Outlook rules, so I couldn't get SpamBayes and other rules (like "when I get e-mail from this address, move it to this folder") to run at the same time. I have not tried to use it with a POP3 e-mail account yet.
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