Later this month, the 2012 Olympics kicks off in London. With hundreds of thousands of people expected from overseas, is this the perfect trigger for a pandemic? This week we're looking at the public health implications of events like London 2012. We discover why an understanding of crowd psychology can avert disasters, and how mathematical models can predict and prevent jams in human traffic. Plus, a new technique to communicate with "locked in" patients, the evidence for warm blooded dinosaurs, and does ice really help to treat an injury? Like this podcast? Please help us by supporting the Naked Scientists