Drobo - automated storage you don't have to manage.

As media (photos, video, movies, music) continues to eat up your hard drove space, you need a solution that allows you to easily manage, protect, and scale storage for your PC or Mac. Now there is Drobo, the first fully-automated storage robot to take the pain out of keeping your important digital content safe. I just bought one of these and it is an automated backup without the hassles.
You can read more at the website (link). There is a very informative demonstration video at the website, worth watching.