Everyone dreams of traveling. It isn't always a practical descision to drop everything and leave.
Machu Picchu is certainly a top pick. Many places are breathtaking but those that have visited the pyramids have never been dissapointed.
One of the big thing in Japan is to never tip. It may be considered polite and something everyone does where you are from but it is not acceptable there.
The biggest culture shock is how pedestrians act. In San Francisco you see people just walking across the street. Weaving in and out of crazy drivers as if it does not even matter.