Here is my questions and situation. Moving from an older Windows laptop to a MacBook Air. The only thing I really keep locally on the Hard Drive is my iTunes library. So I considered just moving it to an External Drive and plugging in when I need it. However, I also use iTunes in the Cloud. So, lets say I am out and about, and want to download one of the songs or Movies I have, but don't have my External Drive. What happens? Does it download a second copy locally? Wouldn't it be looking for my Est Drive as the location of the library anyway? Where would it download to? WHat happens when I plug the External back in? I'm just trying to manage a library bigger than the HD on the Air. Unfortunately it would be my primary and only computer.