Read this article in today's New York Times: Is happiness catching?
James H Fowler and Nicholas A Christakis have published quite a few papers on social networking and how it affects the behaviour of people. A couple of papers describe the patterns in gain of weight and smoking habits of residents of a town Framingham during the period of 30 years. Their findings suggest that these changes do not occur randomly but in clusters or groups of people who are socially connected. I was not surprised to learn that smoking habits spread in this manner. But I had not thought the same way regarding some other parameters that they studied including "happiness". They report that unhappiness or happiness extends upto three degrees of separation, e.g. friends of one's friends' friends and this part of their work has been questioned by many in the same field. I would like to read some of their papers which have been published in high impact journals like NEJM and BMJ.
I find such research work which deals with social behaviour and psychology very exciting. Will see if I can get involved in any similar project sometime in future. But my current research work doesn't provide me with any expertise which will be required for this slightly distant field. :(