The Daily News lists some urban legends and their truths. The story Gothamist likes best is this one, about dropping coins from the Empire State Building:
Urban legend: Coins dropped from the top of the Empire State Building can kill pedestrians below or embed themselves in the pavement.
Real story: The aerodynamics of the skyscraper create a hefty updraft that blows any tossed pennies against the building; they generally land on the 86th-floor window ledges.
Thank God. We dropped a penny way back when we were 8 and have been worried ever since.
There may not be crocodiles in the sewer system, but there was an alligator in Queens recently.