MozBackup - Backup tool for Firefox and Thunderbird
imapsync - Console-based utility for migrating IMAP mailboxes.
Clumio - Clumio is first-in-class cloud backup optimization and visualization engine that provides a chance to top leading business organizations or enterprises to protect, delete and restore their precious data in no time.
mnIMAPSync - mnIMAPSync - Java IMAP email syncing tool
MySQLDumper - MySQLDumper is a PHP and Perl based tool for backing up MySQL databases.
MailStore - MailStore Home - A 100% free single-private-user desktop solution