His film Midnight in the Garden of Good and Evil has a fantastic jazz soundtrack. Set in 1930's Savannah, and about a murder that happened on the estate next door to that of the jazz songwriter and legend Johnny Mercer, the soundtrack is filled with his marvelous tunes--including Eastwood himself singing the classic "Accentuate the Positive." I can't speak to the film, which I've never seen, but I love the soundtrack.
Alas, the soundtrack is not on Youtube, so I can't share any of it with you. But here are some classic clips of Johnny Mercer and some other celebrities:
And my very favorite Johnny Mercer song (and its best version, by, of course, dear dear Ella.)