Rats have a rough life in the Big Apple. They are feared, even hated. In many subway stations there are signs warning people to be careful because rat poison has been sprayed in the area. A few months ago, I walked into a subway station and watched a rat that must have been about three quarters of a foot long just walk around as though he owned the place — with no problem. That was not the case last Friday, when people in Penn Station proved that even though we have passed the time of the gladiators, the mentality has not left us.