Our number-one-software is Yadis. It's an easy-to-use backup-tool, which will save you a lot of troubles. It guards your personal data by making real-time copies (whenever you make changes to your documents) to almost any destination you choose. You do not need to schedule. Whenever you make a change, your data is saved. If the backup destination is not available then the backup is postponed until the destination becomes available again.
What's new in this version:
Version 1.9.8 adds Drive Health Check notifier. Filter events can be specified (Size, Attributes). Backlog files and folder are now deleted to if the task is deleted. Asynchronous drive type detection.