Growing up and shooting film, I was always frustrated by taking pictures at night. At the time I was stuck with consumer level point and shoot film cameras with maybe an 800 ISO color film. I didn't know about pushing film or developing. Now as an adult with real equipment and pushable B&W film that I develop myself, shooting at night is a breeze. To begin with, I rarely worry about my light meter readings at night, since the meter will usually try to compensate for the low light, always aiming (as it should) for a well exposed scene. There is one exception: if you are using a tripod, then the light meter will be your friend. You can trust that it will give you a nicely exposed scene and you won't have to worry about a shutter speed that's too low for a handheld shot.
If you are shooting handheld then the meter at night will usually suggest a shutter speed that you can't physically hold still enough to avoid blur or shake. I do try to stick with the rule of keep your shutter speed equal to or greater than the focal length of the lens you are using. For example, don't try to use a shutter speed of 1/30 for a 50mm lens. If you are using a 28mm lens though, you can get away with a 1/30 of a second exposure.
Couple at Night Walking Down Freeman's Alley, Lower East Side
This was one of those instances where a light meter would be pretty useless. It would try to give you a fairly well lit scene and ask you to use a ridiculously low (for handheld anyway) shutter speed of like 1/8 of a second. I set the FM2n at 1/125 to account for the movement of the couple (1/60 would have been better, but they were walking) and used the fastest lens aperture of f1.4. I also wanted an inky black mass on the right hand side, rather than a weakly lit wall. If I would have used 1/60 or pushed it and tried to use 1/30 then that inky black would have been lighter and wouldn't provide such a contrast to the couple walking towards the light.
Schillers Bar Sign, Lower East Side
There were people milling about in front of Schillers and I didn't want to highlight them. I deliberately underexposed this shot, knowing it would cast the people in dark shadow while giving the neon sign more contrast and definition.
Kate Waiting to Cross Second Avenue, East Village
I used the widest aperture of the 50mm f1.4 Ai lens here to get nice bokeh from the traffic lights in the background. The shutter speed was 1/60 since Kate was standing still.
Kate Easting Chikalicious, East Village
Same settings here as the previous picture.
Alias Restaurant Facade, Lower East Side
In this one, I had to use a slower aperture of f2.8 to retain some detail at a distance. In order to compensate for the low light, I used a (probably too slow) slow shutter speed of 1/30, which breaks the shutter speed/focal length rule. It's not tack sharp, but then again tack sharp is sometimes boring.
Man Reading Newspaper, Chinatown
The light here was very gentle and I intentionally underexposed the negative to give it a soft, diffused quality.
Kate in the Glow of Coke Machine, Williamsburg, Brooklyn
Didn't even pay attention to my light meter here. It would have given me a negative with a much too bright light from the coke machine. I just set the aperture to f1.8 and the shutter speed to 1/60 of a second, which is perfect for a 50mm lens.
All images were taken with a Nikon FM2n and a Nikkor 50mm f1.4 Ai lens on Kodak Tri-X 400 film exposed and developed at 1250 ISO in Xtol Developer for 8.5 minutes.