Here's a smattering of Film Trailers that I think function as art on their own weather they promote the story or provoke the audience the marriage of image and sound in these brief clips are to me, ecstatically effective and evocative.
Take a look at these four clips and their use of the music.
Revolutionary Road / Nina Simone
Watchmen / Smashing Pumpkins
Chansons D'Amour (Love Songs) /various films a musical