There's a new movement in psychology -- instead of concentrating on the negative feelings things that make people sad, depressed, or angry, some psychologists are now looking at what makes people happy. These "positive psychologists" have determined that there is a difference between actions that just make us feel good (i.e. eating your favorite food) and selfless actions that make you feel good by doing good (i.e. giving blood). To get the whole story, check out this article in the New York Times Magazine, Happiness 101 .