Crashplan is an automated backup application that performs a differential backup and sends it to another computer over the internet. That is, it only sends what has changed instead of a full copy every time.
Ideally, the setup should allow going back in time either days, weeks, or months. The setup should allow also restoring to a new computer in case the old one is a complete loss (ex. fire, theft). There's OpenERP data in different areas of the computer: database, core application, addons, config files, etc... Also, it should be possible to restore only one OpenERP database at a time, from all those in the past.
There are other Q&A here that address performing an automated Postgresql database dump. Since, Crashplan performs a differential backup, it would backup all the dumps instead of what has actually changed in the database.
What folders should crashplan cover? Should crashplan cover the raw Postgresql data folder? This could allow crashplan to perform the differential and send only what has changed but it limits the recovery to the entire Postgresql data rather than a specific database.