battery pack

As some one who rocks their iPhone naked with AppleCare +,,, I have found that the MagSafe battery works best with a case on. I have also found that I love the contrast of the white battery with a colorful case! Here's my red leather case with the battery pack, post your case and MagSafe battery...

Quick question, I was reading about how the new macbook pros can have pretty short battery charges. Since I plan on taking my computer with me to school (which is 9 hours) when I get it, could I buy an external battery pack to keep the computer charged throughout the day without having to...