It may sound weird that you have to learn crossing the street. Once you set foot in Vietnam, especially cities like Hanoi or Ho Chi Minh City, soon enough you will understand why. The traffic in major cities is a nightmare for many, including Vietnamese. Chances are, you will see people cross the street anytime they want instead of walking all the way to the zebra-crossing.
Thanks to the advancement of technology, you are wired to the world from almost every corner, unless you choose not to. When you are on your trip, it is understandable that you need to log on to the net to keep in touch with family, to update your travel blog and to check your bank account balances.