When I get my mac, I am planning on upgrading the Ram from 1gb to 2gb, and i am also thinking about adding some hard-drive space, so I have a few questions... 1) How do I upgrade\add a memory\ram stick? 2) Will the warranty still be valid after I upgrade the ram? 3) What is a good external HD? I am looking for a cheap one, maybe 40gb-80gb, I found a 40gb one for for $50, then I found a 300+ gig one, for only $100, so idk which to get... I will spend up to $100 (before tax) I am thinking of this external HD, Seagate 250GB FreeAgent™ Desktop Drive it is only $60 (after $20 rebate), it is the best selling external HD from circuit city, Does anybody here have this HD? or have any experience with it?