It's not so much a 'fight scene' as it is a 'civilian running through a fight' scene, but I'd say the extended take at the end of 'Children of Men' is worth a reference here. You've got all this random chaos, a back-and-forth 'flow' to the fight that can be observed without much of the actual fights context, and (unshown) a moment after this there's a final large explosion from a missile or mortar or something that serves as a finale of the section. It's very impressive to watch.
More 'fight scene' actually--albeit memorable more in a 'one-liner' and as the capstone to a neat movie itself is the one in Air Force One.
Which I reference mainly because the movies few action sequences are fun themselves and this one finishes the hand/gun-fighting off. It's basically 'Die Hard in Air Force One' where McClane is the President and...I dunnow, the sets being limited and reused and everything being very contained and cramped because it's supposed to be an aircraft cabin always seemed neat to me. In every fight in the movie, space plays a role in what happens, so this final one completes that by opening up a big 'space' that gets used for body disposal