NYC does not clean its subways especially well. While standing on the platform at West 4th St, Manhattan yesterday, I was amazed at the amount of diverse garbage lying between the running rails.
BTW Rob (sorry off topic), I was there once again trying to catch an old model F-train, and again no luck. I waited thru 4 trains before giving up and riding a different line for the day.
BTW, West 4th is a great station, I believe the busiest in the system. At the head-end of the Downtown (6th Ave) B-D/F-V platform is a manned signal tower. You can gaze thru the window at the operators and their 1930's era interlocking machine with the big levers, and the lighted model board above it. I tried not to be too obvious though; wouldn't want to be mistaken for a terrorist !