Alex Cook made this costume for his nephew for Halloween.
I asked him what he was going to be for Halloween and he said, "A train!" and then immediately specified with "A green line train!!!" My sister had to tell him he was just going to be a normal train since she didn't have time to make one and couldn't find a green line train costume to buy. So I started on my quest with a $1.50 moving box and some duct tape.
Via Boston Reddit.