Name That Slime: Disgusting Fifth Ave. Sidewalk Mystery

What is that stuff? We came across it in front of Brooklyn Fish Camp over the weekend, giving off an indescribable scent mixed with some sort of cleaner. People saw it, stopped, sniffed and walked into the street to avoid walking through it. Some brave souls walked through the watered down megabarf-looking substance. It looked like it might have come from some sort of nasty cleanup at the restaurant, though there is a chance it could have emanated from elsewhere. One person said it wasn't the first time the sleaze had been out there. All we can say is that it was some of the most disgusting stuff we've seen on a sidewalk in a long time (putting aside blown chunks and crap) and that we opted to walk around it. Anyone with knowledge of the vile Fifth Avenue Slime, do let us know.