I haven't been to many countries outside the US:
Mexico
Canada
France
Senegal (very briefly, I had to leave earlier than planned - I intend to go back someday).
Most significantly - I lived in Cameroon for 4 months through a study abroad program while I was an undergraduate. It was the most amazing experience ever of my whole life . . . etc, etc, etc. :D I get very nostalgic about it - it was 5 years ago, and I will still go on and on about Cameroon if someone asks me about it. :p Sometimes I still even have dreams that I'm there. Perhaps I should go back, but it felt so stressful and unsafe (also I was in the city), that I don't really want to go back. Too much corruption and uncertainty - plus traveling as a young woman in west and/or central africa is something else (the stories I could tell!)
And to anyone who hasn't already graduated from college (university) and is thinking about doing a study abroad or exchange program - my advice is DO IT. No matter what country you are interested in going to, you will have an amazing and unique experience. It is one of the best opportunities you might ever have to travel and really experience another culture. I guess that advice is mostly for Americans - I don't know what university and study abroad and all that is like in other places.
