Gmvault - Backup the emails in your Gmail account.
MailStore - MailStore Home - A 100% free single-private-user desktop solution
Datto Backupify - Protect your business with backup.
SysTools Gmail Backup - Backup Gmail Emails, Contacts, Calendar, and Google Drive Storage File by SysTools Gmail Backup Solution
Beyond Inbox - Beyond Inbox, backup tool to backup, copy, move and restore email messages of your IMAP account...
Got Your Back - Got Your Back (GYB) is a command line tool that backs up and restores your Gmail account.