I've used the subway systems in London (Underground) and Tokyo (Metro), but neither have nearly the amount of insane people as New York City. I'm not talking about the casually insane people, the people who smell strange and look crazy, I'm talking about the insane people who scream at themselves the entire ride.
I asked Katia once why NYC had so many people riding the subway and buses who were clearly in need of serious medical and psychiatric attention, but why this wasn't really the case in London and Tokyo. She thinks it has to do with the fact that in NYC, there just isn't enough help for these people, but in other places there might be. I'm honestly not sure what the problem is, but it is definitely a problem.
This morning on the subway I listened to a man scream at himself in Spanish for twenty minutes, all the while filling the car with the smell of his own urine. The unfortunate thing is that I didn't really have a choice—I had to stay in the car because the L train's service is so poor lately that if I didn't get on that train I would have been really late to work (and the other cars were packed). I kept wondering how long you can stand in a place filled with the stench of urine before you start to smell like it yourself. I imagined getting to work and walking into a meeting and people yelling out, "Good god! Have you pissed yourself? This meeting is adjourned on the grounds of stench!"
That didn't happen, but it could have.