But in the world of the subway buff, the three separate systems live on in much of their old glory.

As aficionados often are, subway buffs tend to be avidly devoted to one system or another.

To outsiders, the world of the true subway buff, or rail fan, as many like to be called, has never been easy to understand.

Michael Vincze is perhaps the most isolated subway buff of all.

But subway buffs complain that the new cars are much less fun.

Happily for subway buffs, some Web sites contain unofficial schedules of the new cars' comings and goings (see http://www.nycsubway.

One well-informed passenger who cannot understand the lower speeds is Stan Fischler, a Brooklyn-born subway buff who has been traveling underground for six decades.

The newspapers frequently label him a "subway buff".

They are the smallest subway buffs.

The other day a group of extraordinarily knowledgeable subway buffs were debating a more subjective and much less desirable distinction: the ugliest.