Gamers turn cities into a battleground

Matt has been abandoned on Tower Bridge, London, with nothing except his clothes and a mobile phone. A woman dressed in black walks past, and Matt receives a text message to follow her. He doesn't know who she is, or where she is going. All he knows is that he must follow her if he is to find Uncle Roy. Matt is playing Uncle Roy All Around You, where for one day he is the main character in an elaborate experimental fantasy game played out across the streets of London. He also happens to be a pioneer of a new social phenomenon, urban gaming. If you thought the computer games of the 21st century are only ever played by couch potatoes addicted to the new generation of Xbox, Nintendo or PlayStation consoles, you'd be mistaken. For urban gamers are harnessing the power of global positioning systems (GPS), high-resolution screens and cameras and the latest mobile phones to play games across our towns and cities, where they become spies, vampire slayers, celebrities and even Pac-Man.