imapsync - Console-based utility for migrating IMAP mailboxes.
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.
Gmvault - Backup the emails in your Gmail account.
MigrationWiz - MigrationWiz provides on-demand mailbox migration services through a fully automated cloud-based...
Cryoserver - Cryoserver is an all-in-one email archiving solution that empowers you to preserve your email in a tamper-evident archive, making you transform your data into a useful archive for everyday use.
IMAP Upload - IMAP Upload is a tool for uploading a local mbox file to IMAP4 server.