Based on my travel experiences, the most useful thing that one should always bring is a camera.  For so many times, i tried to bring books, but it just add weight to my luggage. I don’t have time to read it.

You may say, you can read it while weaiting for the plane but the problem is I always tend to be busy looking around for new stuff that around me, or I’ll be busy searching for food to eat;  and aboard the plane, I’d rather sleep or get photos of the clouds or the place below;  upon getting at the destination place, I’d walk around and go back to the hotel already tired, so there’s no really time for me to read.  It’s a good thing that I didn’t bring books with me to Australia this time.