When we take the subway, we riders typically don't use our commuting time enjoying the scenery. We read books, chat with a friend, or play a game of Angry Birds, but look around the station? Nah. While on the Coney Island bound F train, I decided to look up while waiting on the platform. I discovered this: After 7 years using my local station, I finally saw this sign, circa 1940's by The Subway Sun. Turns out the Subway Sun has been around since 1915, teaching riders proper subway etiquette. 12oz Prophet has a great collection of old ads, as well as Joe korner. Another…