I've been playing The Long Dark recently and that game offers an option to 'Dampen Camera Movement'. Explanation:
The Long Dark is a First-Person survival game. Usually, when moving your mouse, your input is translated 1:1 onto the screen. With that option from the game enabled, the camera changed direction in a trajectory-like path, accelerating into the direction the mouse has been moved into instead of just exactly moving to that place. Another example for that feature is a game called Darwin Project. When playing as Show Director, the player takes the role of a god-like drone. Changing the direction that the drone looks into is done with the mouse, as usual, but is damped, just as in The Long Dark.
I would like to have such mouse movement as a global setting on my computer, because it feels very smooth and is nice to look at.
Note: It just came into my mind that stuff like that will probably include something with drivers or so. Right now I am using a Roccat Kone XTD, utilized by the default Windows 10 driver. I am running on 64 Bit.