There are different goals and motivation:
1. Exotic adventure - Africa, Nepal, Tibet, the Caribbean, Indochina, India
2. Politics - Washington D.C. as congressman's aide
3. Humanitarian and wildlife projects - Africa
4. Linguistic immersion - whichever country is right for the language of choice
5. To stay with some rich friends and play - wherever the friends may be: Dubai, Rio, Beijing, Monte Carlo, Florence, Paris, New York …