I have a Mac Pro that has all 4 bays full. Two 500gb drives, a 1tb drive, and a 1.5tb drive. They're all full up! Yup! I need a way to put as much of the data from all of the drives onto as few drivs as possible. I calculate 3.5tb, so two 2tb drives would do for now and I can expand to four 2tb drives or larger drives in the future. So how do I go about simply automatically merging the data from multiple drives to one?