No such thing as a free lunch, is there? China's Huawei has generously offered to pick up the roughly £50 million ($81 million) tab for equipment to line London's sprawling subway system with mobile phone reception, a package it says it's extending as a gift from Olympic host nation to another (London will host the 2012 Summer Olympics, and it has said in the past that it'd like the Tube wired in time). The official line is that Huawei would make its money back over time through maintenance contracts, but some politicians are raising red flags over the Chinese firm's