The consensus is that New York's Lower East Side stinks. This is not an analysis of the neighborhood as a whole, it refers specifically to its stench. Its putried smell is so famous, that fragrance company NOVA combined the "decaying rat, detergent, dog, sweet BBQ" and "standard stink" to accurately create the Lower East Side perfume.
NOVA boss Julia Zangrilli advised Gothamist to give the scent "a full 10 minutes" to permeate, and Gothamist confirmed that, yes, it has the authentic LES stink. If you want to be cruel, crack a bottle open in a crowded elevator and watch the magic.
Just be prepared for the odor to burn your nostril hairs and bring tears to your eyes.