I've had one, it was pretty epic. I was playing on continents (two) on a large map, standard speed. Basically, I was able to conquer the continent I was on, and Korea conquered the entire continent it was on. Once we both had control of our continents, we were both just producing units as quickly as possible. Korea might've been 1-2 techs ahead of me, but I had a larger military, especially my navy which I needed to launch a large scale invasion of his continent.
Before I started the war, I had several spies in his cities so that I could track where his nukes were, so I nuked those and tried to capture them first (I had a fleet of nuclear subs setting near his coast.)
Unfortunately, I was not able to destroy all of his nukes with the opening salvo. He used 1-2 nukes against my troops on his first turn of the war. But beyond that he didn't get a chance to use any more because I was tracking his cities with spies/making sure I had visibility, so I could see if he either had nukes, or was producing them and I always took them out before he could finish building/use them.