It's basically an audio time machine. Tech historian Emily Thompson, out of Princeton, has put together an interactive map of New York circa 1933, embedded with the old sounds of the city.
The map uses a combination of noise complaints and old reel footage to plot everything from what must have been an exceptionally noisy subway turnstile (complete with notes from the police report) all the way to a carnival barkers in Coney Island, and is a great way to listen in on the everyday life of a New York City gone-by. You can check out the full interactive map in Vectors.
But it also raises another question: What kind of sounds would you capture to put together an audio map of life today? Give us your nominations for the ambient noises that best capture everyday life in your own locale in the comments now.