If you’re lucky enough to have a cinema nearby that shows certain films on actual film stock then I can’t recommend it enough.
All of the mistakes and signs of use on the film stock, that are apparent to you throughout the runtime, adds another layer of immersion to a cinema experience. No one else will see that particular showing of that particular film except for the people in that room with you at the time.
One of my old drama school teachers once told me a fun little story about the gaps between each frame. He said that all those empty gaps which are only fractions of a second between frames being processed and projected are all registered in our brains when we watch a film on celluloid. He also said that our brains see these blank spaces and instinctively imagines what would fill the empty gaps so, we feel more immersed in the film as our brains try to connect these dots in front of us.
I don’t know if that’s true at all, but I’d like to believe so.