Lets be clear about something: it is NOT illegal to photograph inside the NYC subway system. They may raise a fuss about tripods though, on the grounds that it blocks access. Otherwise, normal hand-held photography is NOT, repeat NOT illegal in the NYC subways. It NEVER was illegal either. There WAS a proposed law which would have made photography in the subway illegal, but the law was not approved. So, if anyone -- ANYONE -- comes up to you and tells you to put your camera away, remind them of the First Amendment which gives you every darned right to photograph buildings, trains, subways, tunnels, etc. and if they say its illegal, ask them "What law says so?"