Travel.

I love this picture (it's in Portuguese). It says "You want to be happy, don't buy any more things, go travel". I completely agree. We should all stop and think about all the money we spend buying material things that we don't need and only want. Traveling will teach you things that a textbook can't and it will give you the experience of a lifetime. Everyone should get to experience what it is like to be in a foreign land exploring what to you is unkown.