I just found this project on Behance. It is by Amanda Mocci and is no other than a series of drawings of people on the train.
“I would carry my sketchbook with me everyday and draw people I find interesting. I would then associate the people with adjectives. After that I would come up with an imaginative phrase that goes with their appearance and what they might be thinking at that moment.”
I think it's awesome, the drawings are really simple and look very sketch-like, giving you that feel that it was for sure done while on those fast, short metro trips. The best part of it all is that she was brave enough to show her judgment of other people. We usually keep it to ourselves.