Since they mostly feature plaintive images of missing pets or the services of dodgy-sounding handymen, signs stuck up on the streets of London rarely do much to lift our spirits. So this one which appeared on a post in Stoke Newington is a welcome relief. In the note, its anonymous writer thanks three men for... well, maybe just read it. The guys who are mentioned are an equal mystery. But are specific names and identities that important? The simple fact that this happened at all is enough to have provoked a warm response across the Twittersphere. In these fractious and divisive times, and a city where we're forever surrounded by strangers, this feels like a little piece of proof that city folk may be many things, but on occasion they do look out for each other in times of trouble. Be proud of yourself, London! We are.