Less "I'm on the train", more mime on the train...Japan's pioneering mobile phone network NTT DoCoMo is developing a mobile phone handset that can lip-read to cut down on noise pollution. A Japanese company is researching a handset that reads the electrical impulses that come from the caller's facial muscles, and silently converts them into text. A caller can then mouth the words to their conversations, rather than speaking out loud and forcing anyone nearby to listen to them. The technology has already been refined to work with an "acceptable error rate", and it's likely to be available to consumers within five years, the New Scientist reports. NTT DoCoMo already has a prototype ready. Japan is far more sensitive to public mobile phone use than the UK - some transport networks ban the use of mobiles altogether, and normal etiquette requires a hand to be held over the mouth during mobile conversations to minimise public annoyance.