Postini is an E-mail and Web security and archiving service owned by Google since 2007. It provides cloud computing services for filtering e-mail spam and (before it is delivered to a client's mail server), offers optional e-mail archiving, and protects client networks from web-borne malware.

Postini can be used as a additional backup and recovery system for your google apps. It can support the paid, as well as the free version.