MailStore - MailStore Home - A 100% free single-private-user desktop solution
ifttt - IFTTT puts the internet to work for you. Create simple connections between the products you use every day.
MailSteward - MailSteward : The Ultimate E-mail Manager for Mac OS X
ExpanDrive - ExpanDrive is a fast network drive and browser for cloud storage.
Gmvault - Backup the emails in your Gmail account.
FileCloud - FileCloud is an enterprise file share, sync and mobile access solution.