I always take a backpack when traveling.  I find them to be the most useful piece of luggage that I have once I arrive.  The first trip that I ever took with my Ghurka was to outer space.  Or at least as close as most of us will come to it.  I packed up everything I needed for my day in the backpack and was off to Cape Canaveral.  It was a fun day of exploring and discovery about the development of the US space program.  And my Ghurka provided all of the supplies that I needed throughout my day.

The backpack provides all of the storage that I need with convenient pockets and space that I need for storage of a day's worth of fun.