I spent last summer in Berlin, and am planning to go to London/Edinburgh in the fall.
Berlin was such an amazing experience. Just "being" in a new environment is an incredible way to learn about yourself. When you're forced to adapt to an entirely different culture and way of life...you encounter yourself through the process of changing.
You also realize that, as much as people like to say that "we're all the same," as much as people like to minimize differences between people, they are just as important as our similarities. Yeah, Germans drive on the right side of the road, drink beer, and love sex just like us Americans. But for them, driving a car is an intensive experience; nobody talks while they're driving. Ever notice how German cars don't have enough cup holders? That's because a German wouldn't think about sipping an iced coffee while driving. He's in his car, not his living room. A German would laugh at what we consider decent beer. Beck's is about the shittiest brew you can find in Berlin; for us, it's pretty good. Germans also get plenty drunk, but they do it sitting around a table at a bar with their friends, not standing up and walking around a bar hitting on girls. Germans fuck at a younger age than most Americans...remember losing your virginity to your girlfriend? In Germany you find a curious girl, screw, and move on.
Obviously this is pretty focused on Germany, but this is just scratching the surface. The same goes for every culture globally. Your experience of interaction with others will teach you so much about not just them but about yourself; you'll naturally compare the foreign things you observe to the aspects of your own way of life that you never considered.
So yeah. Definitely study abroad. Definitely do it for an extended period of time. Make sure that you also spend the majority of it in one place; you'll see so much more if you root your experiences to one way of life.
Ohh yeah, and you'll probably take classes. Those are fairly useless; man learns by seeing the world around him, not by being told how things are.
A life for the night / Dear Lord, you've took so many of my people / I'm just wondering why...
Doug. Shane. CR. Rest peacefully, skiers past.