Western Digital has today made backups of your precious data even easier by unveiling their WD SmartWare Pro app. The backup app automatically backs up file changes to a local drive when it happens, and it can schedule backups to the drive and a Dropbox account.
You can be even more cautious, and backup the Dropbox account to the external HDD. The nifty backup app isn't limited to WD-branded drives, so any external storage will do. You'll spend $30 on a three-computer SmartWare Pro license, which isn't too bad for your data backup needs.