Just once.
I was on the way home from the 1958 assembly at Yankee Stadium. We were aboard the "Arosa Sun" and sailing from New York to Plymouth, England. The ship was pretty well 50 - 50 split between British and German.
When we arrived at Plymouth, the British contingent disembarked whilst the Germans stayed on board to continue on to Bremerhaven. The Germans were lining the decks of the ship waving goodbye to us.
Suddenly, we heard a faint singing from the bow end of the ship. Then it spread right along until the whole vessel reverberated with the song.
It wasn't a Kingdom Song either. It seemed that the whole of Plymouth Sound was ringing to the strains of "Now is the Hour".
Now that was emotional.
I've come over all teary-eyed now...I think I'll go watch Casablanca again..
Englishman.