We have a 15" PB (first mac purchase) and plan on getting a powermac for our large family. We bought FCP and need more disk space on PB and want to share the external disk with PM. Several questions: 1. Can we get external storage that will work with FW 400 on PB and FW 800 on PM? 2. What size HD is the best performance/value? 3. Best manufactures and place to buy? 4. Suggestions on HD size we buy in PM. Are we better off getting as small HD as possible in PM and sharing it with PB? 5. Just thought of this. Can we use internal storage of PM with the PB? How would you hook it up through FW 400 on PB and it just looks at it as another drive? Is the PM drive compatable with PB FW 400 connect. Just learning so I'm sorry if these are basic questions. Thanks for the help!