Best Mail.app friend. All you messages in menubar.
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MailBar is a practical Mac OS X application that enables you to check your inbox and manage your emails directly from your Mac's status bar.
The light and discreet application is designed to run in the background and display the number of new emails next to its menu bar icon. Thanks to MailBar, you can monitor and manage up to four different mailboxes. From MailBar's status bar menu you can easily view all existing emails or filter the list by showing only the unread messages. On top of that, MailBar comes with a powerful built-in search form that enables you to narrow down the list of displayed emails.
MailBar provide all common Mail.app functionality right from status bar. Benefits of using MailBar its saving of you time, and every day you will use MailBar more time than Mail.app