The musical score of The Sting (a great movie, I agree) was notable because of the orchestral arrangements of Joplin's music, which of course was originally written for solo piano.
Interestingly, ragtime had been out of fashion for 20+ years by the time of The Sting's setting (early 1930's). I also love ragtime and associate it with The Sting as well though, it's just amusing to think that our association between the music and the era was made up by George Roy Hill.
I also associate it strongly with 'The Sting'. An old movie, but a great one.