imapsync - Console-based utility for migrating IMAP mailboxes.
MigrationWiz - MigrationWiz provides on-demand mailbox migration services through a fully automated cloud-based...
Fetchmail - The Fetchmail Project
MailStore - MailStore Home - A 100% free single-private-user desktop solution
IMAPSize - IMAPSize
isync (mbsync) - mbsync is a command line application which synchronizes mailboxes.