The high-tech scanners that can home in on chemicals produced by cancers, how bats and dolphins share genes for echolocation and why barefoot runners have a smoother track record. Also this week, augment your reality: find out how new technologies can add extra information to the way you see the world by making a mobile phone into a virtual tour guide or even a pocket mechanic! Plus, how virtual reality worlds are helping to rehabilitate stroke victims, and, in a theatrical twist, for Kitchen Science Dave discovers the workings of a baffling stage illusion... Like this podcast? Please help us by supporting the Naked Scientists