I have a macbook unibody running leopard, 150g hd and i only have about 850 mb left on it.. i have a lot of pictures music and hd videos from my iphone and hd flip.. i also had made a bunch of imovies.. i bought a 1tib western digital external hd so i can free up some space on my computer.. i backed everything up on the external.. now my question is if i keep my external drive plugged in cant i just delete all the stuff on the computer such as music,photos and videos to free up the space on my hard drive.. ?? i know you cannot delete programs on the mac and try to run them from my external.. but how can i make my computer access the external hd to get all of the music photos and movies so that all the space on my mac will be free..?? can i even make everything save to my external instead of my mac hd???? and also my computers local disk space is low??? please help...