I just bought the new iMac (love it!!!) but I still have a macbook. obviously, I rarely use the macbook anymore, except for occasional trips out of state, or just to a coffee shop- times where battery life is more important than anything else. (used for internet, e-mail, and microsoft word primarily). my question- how do I get the best battery life for that macbook? should i leave it plugged it... take the battery out...? or any other suggestions. thanks!!