imapsync - Console-based utility for migrating IMAP mailboxes.
Vaultastic - Vaultastic - Simplify Data Protection and Management. Flexibility to do more, cover more risks, and optimize costs.
MailStore - MailStore Home - A 100% free single-private-user desktop solution
MailArchiva - MailArchiva is an email archiving, email compliance, and e-Discovery enterprise server.
audriga Email and Groupware migration - Easily migrate your email, contacts, calendar items and tasks to your new provider or server. No software installation is required.
MailBakup - Mailbakup is an all-in-one IT solution that provides an in-demand set of e-mail backup solution to save valuable data from the web-based email account to location derive easily and quickly.