Greatest Movie Themes

There are lists for "The Greatest Film Scores of All Time” and a list of “The Greatest Movie Soundtracks” but I couldn't find one solely for movie theme songs - the song usually played during the title sequence and/or end credits and often repeated with variation throughout the movie score. For most movies or movie franchises, this is the most iconic song from the soundtrack or score and is often the most recognizable music on these albums. I'd bet that the majority of up votes on those other two list come solely from the popularity or iconic value of the opening/closing theme song.