Mailboxer is a simple app that creates a Smart mailbox for everyone in your Address Book. Sounds like that could be a bad idea if you have LOTS of contacts in your Address Book, but on the other hand, it might be nice to keep all your correspondence organized.

Several days ago the blogosphere was a buzz with news that a certain Terminal command would “vacuum” your Mail folder, shrinking the site of your message database and causing Mail to load much faster. VacuumMail makes this easier by performing the command for you. There are no preferences or options with program; as soon as you open it, it performs the “vacuum” and then your Mail app should perform much faster. You should probably close Mail before running this app.

Highly acclaimed by many books and reviews, POPFile is a spam filter to help keep your email inbox clean. It’s a bit hairy to install on a Mac — you’ll need to get into the Terminal a bit — but once installed, it sits between your email client and email server and separates email from spam using a Bayesian filter. This may not be for everybody, but if you’ve found your current spam protection to be inadequate, this may be for you.