Great article in The New York Observer... The Town Criers.
I've cried many times while walking down a New York City street.
One time I got into a big fight with a guy I was seeing and cried on my subway ride home. The train made a stop in Chinatown, where an older Chinese man got on. When he sat down he saw me crying so he reached into his pocket, pulled out a wad of Dunkin' Donuts napkins, walked over to where I was sitting and gave them to me. It was kind of gross (they were really wadded up) but sweet, so I thanked him and pretended to use them.