I think that one of the most brilliant advertising campaigns of all time is the United Airlines use of George Gershwin's beautiful piece "Rhapsody in Blue" because of the symbolism of the title and the air of elegance, beauty, and worldliness that the piece conveys for United Airlines.

Please, I implore you to view their newest series of brilliant commercials. Fucking best ads I've seen in a long time!

Also check out their cool print ads that I reckon will be considered art gems somewhere down the road. Also, notice the Expressionistic/Modernist style of the UA art that I have included in this post.