I had taken my seat on the train a clear five minutes before departure. The 17.17 to Woking filled up rapidly but I had, through my own promptness and good organisation, gained a double seat. It was a Friday night, the fug in the carriage thick with the body heat and poor odour of desperate commuters, shaking wet macs from their shoulders, shoving bags on to the overhead shelf, snarling into phones. I acted fast, unclipping the little table on the empty seat beside me and placing on it my neatly folded newspaper, my miniature bottle of wine with a plastic cup and a box of cheese and crackers. These things are the treats that signify an end-of-the-week commute for me. It is very important to signal a Friday, I always think: and it's the one day of the week when I really care about having a little elbow room. I placed my briefcase on the empty seat beside me, which now did a very passable impression of a full one.