Spotted this on my walk to the office this morning:
If you can't tell, it's a bus covered with laundry. This had to be an advertisement for something (MTA employees aren't that eccentric) and after a little poking around online, I found out it's part of All's "Spot the Bus" sweepstakes:
From May 15th to 26th, two all small & mighty buses covered in clothes will cruise the streets of New York City. When you see one, send a text message of the time and location to 96787. You'll be entered in the Spot the Bus Sweepstakes.
If you'd like to take part without actually spotting the bus or even living in NYC (and have a chance at winning $5000), I took the above photo at 10:41am near 14th Street and 10th Ave in Manhattan. Good luck!