MailStore - MailStore Home - A 100% free single-private-user desktop solution
Datto Backupify - Protect your business with backup.
MailSteward - MailSteward : The Ultimate E-mail Manager for Mac OS X
SolarWinds Backup - Modern server backup software
Gmvault - Backup the emails in your Gmail account.
OwnBackup - OwnBackup provides automated backups of SaaS and PaaS data and restore tools for disaster recovery.