I don't remember Broadway being so dense with stores that you had to put "1/2" in the address lest the postman deliver Insurance mail to the bakery. What I do remember are the X Marks the Spot signs, a few of which can still be found in the back roads.
They marked the place where someone died in an auto accident. Those things gave me a chill as a kid: a ghostly bone-white and death-black sign pointing a finger at you from beyond the grave. They were often in peculiar spots, too, and the older you got the more you wondered how someone got himself killed there. Couldn't happen to you.