Here's an interesting fact of the day for you.
I think almost everyone knows this really fun song, Funiculi, Funicula.
Composed in 1880 by a man named Luigi Denza, it was for the opening of a funicular railway that ran to the top of Mt. Vesuvius. The song is about a guy in love with a girl named Anna. He's trying to talk her into going to the summit of the volcano with him for a romantic stroll.
Anyhow, the song became a huge hit, selling over a million copies of sheet music within a year. (This is the 1800's after all.)
A few years later, the famous German composer Richard Strauss comes to Italy and hears the song while in Naples. He loves it! Believing it's a traditional folk song, he adds it to part of his latest piece, Aus Italien.
Luigi, the Italian composer hears it and says, "What the heck? That's my song!" So he sued and of course won. From that day forward, whenever Strauss' orchestra played Aus Italien...Luigi received royalties.