if you have a bad back, i don't know if getting a backpack is the wisest thing to do. even if the bag is only used to get you from home to airport to destination, having wheels is generally easier on the back than using a backpack.

that said, ebags makes a couple of backpack type carry-on bags that you can look at for starters. if none of them click for you, their site sells a decent selection of other carry-on/travel bags. the same goes for if you want a slimmer briefcase.

http://www.ebags.com/product/ebags/m...ertible/143101