MailCountX is a tool that places an icon next to the AirPort and clock icons on the OS X system status bar. It displays the number of unread emails in your Mail.app inboxes.
Because short glimpses at the status bar are often enough to keep you alert and informed about new messages without taking you out of your workflow, MailCountX ensures you won't miss a thing while you're working on something else. No more constantly tabbing in and out of your mail client just to see whether there are any new emails!
Overall, MailCountX seems to be a useful and easy-to-use addition to any OS X user's workflow. Whether you're trying to stay on top of your inbox or just want to get more done in less time, this app has you covered.