People-watching on the subways is immensely interesting,and often entertaining, but my favorite thing about the New York subway system is the tile design. We had a particularly long wait at the 81st Street Station after my kids and I spent the afternoon at the Museum of Natural History.
I amused myself, and those who observed me, by taking a picture of every animal mosaic I could find at the station. My teenage kids were horrified to be seen with their loony mother who was obsessed with, of all things, tiles. Here are some samples of those tiles:
You can find more on my flickr account here. Which is your favorite?