OwnBackup - OwnBackup provides automated backups of SaaS and PaaS data and restore tools for disaster recovery.
MailStore - MailStore Home - A 100% free single-private-user desktop solution
SolarWinds Backup - Modern server backup software
Gmvault - Backup the emails in your Gmail account.
Spanning Backup for Salesforce - Spanning Backup for Salesforce is the backup and restore solution delivered directly within the Salesforce interface.
Mail Backup X - Your one stop mail backup and archiving tool for Mac.