Ok so I just picked up a 500Gb WD Studio and I've got two Macbooks at the house that I want to back up/clone. using SuperDuper/CCC, what would be the best way to do this so that I have a clone of both hdds in case of a hdd failure? here's how i'm thinking it works: 1. partition external, one half for Macbook #1, one half for Macbook #2. Make a clone of each partition. or 2. create .dmg files for each Macbook on the hdd and put them on the hdd...my train of thought is that *both* hdd's wouldn't go out at the same time so i could always drag the .dmg to the working one and then mount it there and boot from it via target disk mode (did that even make sense??) My main goal of the ext hdd was to to store my video and pictures on it as well as have a bootable image of my hdd "just in case". Being that this is my first time having an external hdd, i'm a bit confused on how it's supposed to work. Right now it's making a bootable clone of Macbook #1 on my external via superduper. Thanks in advance for any guidance.