I am considering purchasing a Macbook Pro with all of the upgrades and 7200rpm hd to run Logic Expres. I have not used Logic before and have a few questions. Also, I don't know all that much about computers overall, which will probably be apparent, so please bear with me... First, I have been advised to have an external hd for virtual instruments. What exactly does this mean? I am storing a digital library of sounds on an easily accessible hd? How will I access these to put them into the mix? I want to be mobile so I wonder if I will have to carry a hd around with me?? Part of why I think I need this external hd is that my songs get complex, with lots of tracks and lots of effects. I also like to work on multiple projects at a time so I tend to like to confuse computers! Anyhow, clarification on how this would work would be greatly appreciated. Also, what would be the best external hd for storing finished songs or those not in use and the virtual instruments that I mentioned above? Thanks!