I am going to start a competition at our college, where we'll be giving away one iPhone each month for six months starting January 1st. People only need to answer three easy questions, and last year we had about 9000 participants. This time, I am thinking about a way to make the competition go viral. Maybe we'll give away one iPhone to the person referring most people to the competition? I am not sure about the best strategy in order to make the competition viral, do you have any suggestions? Any software we can use? - Jens