With Film camera Nikon Fm2n?

How regular would you use the highest shutter speed?
In what circumstances would you use such setting?
Are there alternative without using such a speed?

When shooting sports or fast moving objects, most of the shutter speeds would be at 1/500th second or faster. It would be a rare situation that you would be shooting at 1/4000th second.

Even now while shooting with sports with a camera with a 1/8000th second top end shutter speed, I rarely shoot at shutter speeds even close to 1/1000th second

There's on time when you can freeze motion without using a fast shutter speed.

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As fhotoace points out, the super fast Nikon FM2n has a top shutter speed of 1/4000th. The faster the shutter speed, the less light you're letting into the camera and the higher your ISO has to be or the wider your aperture must be to compensate.
1/4000th is insanely fast and is not used often by most people. It can be used during sports to freeze motion but usually you don't need more than 1/500th to 1/1000th for that.
What I use 1/4000th for with my FM2n is shooting high speed film in daylight and/or shooting with a very fast lens at wider apertures in daylight.
For example, in the photo below, which, was actually shot with an original FE, I used my 1/2000th shutter speed and 3200 ISO film in the daytime in order to get a very grainy, high contrast look to my shot;
Here's another example:
In the second example, I'm photographing people on the street. High speed film is useful for street photography because you can increase your DoF and ensure correct focus without staring at the viewfinder so long you might call attention to yourself and ruin a moment. Having these higher shutter speeds allows this use.
Another thing you can do is use a lower ISO film in the daytime but use a very wide aperture so as to get, what people are now calling a "bokeh photo"
Here is a shot using an FM and a 50/1.4 lens wide open in the daylight. Again, not at 1/4000th but at a higher speed and the principle remains.
I hope my comments were useful and you are able to make good use of your FM2n. I own three of these for wedding photography. They are compact, flexible, tough and accurate cameras, really wonderful for numerous types of photography!
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