The backpack I purchased for the trip has definitely come in handy. Just when you think you have filled every last nook and cranny there is still more room. However, I am not sure if this is a good thing or not considering I have to carry the bag myself. But it is a lot better than trying to juggle two suitcases, a bag of equipment, and my carryon. Oh.. and yes I did know that international flights allow two bags. It is just that Continental Airlines charges $50 for a second check on even if you are flying international from the US, so I was trying to get as much as I can into one suitcase, a backpack, and my carryon.