I’ve stressed it before, and will continue to do so – backing up your data on an automated, regular basis is crucial. Here’s my current setup:
Backblaze. Continuous background backup service.
CrashPlan. Continuous background backup service.
SugarSync. Data syncing across multiple devices – not really a backup solution, but lets me easily access my most important files wherever I am.
Carbon Copy Cloner. CCC is doing daily incremental backups to three external drives.
So three cloud locations as well as three (local) physical locations. Dropbox is also used for the most current projects, but since moving to Mountain Lion I’ve started rely on the iCloud sync provided in several applications – not really backup in the traditional sense of course, but it makes keeping on top of things really easy.
