Mac OS X: Two years ago we showed Windows users how to upload old and archived email into their Google Apps mail account. Now the same functionality is available for Mac users.
Google Email Uploader for Mac is the Mac-centric version of the Windows version we've previously introduced you to. Like the Windows version Google Email Uploader for Mac helps you take email you have archived on your computer and insert it into the Google Apps mail account. Google Email Uploader supports Apple Mail, Eudora, Thunderbird and other applications that use mbox or Maildir archives to store email.
Check out the link below for additional information and if you know of other applications or clever tricks for migrating old data into your Google accounts, let's hear about it in the comments.