Eudora's amazing new spam filter
Thankfully, Eudora 6.0 (still in beta) has a new Junk feature that works incredibly well.
I've been using Eudora for years, but when Apple's Mail application came out with a Bayesian filtering feature, I immediately gave it a try. I was very disappointed to find that after several weeks of learning it kept missing a pretty high number of spams (more than my custom filters in Eudora), so I didn't make the switch. Now I'm glad I didn't!
As an Apple supporter I hate to say it, but I find Eudora's Junk feature (also based on Bayesian filtering) much, much better than Apple's: it has no "learning" step, and as soon as I enabled it, it caught more than 95% of the 150 spams or so that come daily into my Mac, with (relatively) very few false positives. And now that I identified these false positives as "Not Junk" and updated my spam filters (changing their action from "Transfer to the spam mailbox" into "Junk"), Eudora catches very close to 100% of the spams with 0% of false positives!
I know that sounds incredible, but it's true. Their new Junk feature is amazing! For several weeks Eudora hasn't missed more than one spam every two weeks, or something like that, and I stopped looking for false positives in the Junk mailbox a couple of weeks ago, because I never found any.
So if you're not completely happy with your current email client, I strongly suggest you to give Eudora 6.0 a try (if you can stand its multi-windows-interface, that is).