I have a couple of email accounts which I check on my Mac using Mail.app. The problem is like many I get a lof of spam through out the day. I already trained Mail.app to spot junk emails but its not perfect and so I decided to find a better solution. A while back I found a software called JunkMatcher. JunkMatcher is a software that integrates with Mail.app. It gives you a lot more junk mail options and it already comes built-in with a whole set of rules. With my upgrade to Tiger, JunkMatcher stopped working but recently they updated the software and now its Tiger compatible. So download it and try it, you won’t even notice its there. [Link]