What's your favorite album cover art ?


While re-organizing my album collection, I found myself admiring the quality and beauty of the album cover jacket. One artist that really caught my attention was Roger Dean who did all (most) of the YES cover jackets. You just don't get this quality of art on CD jewel case inserts. What are your favorite album cover jacket art?
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I used the Roger Dean covers in the 70s behind an aquarium as the fit was perfect (15 gallon?), and they looked the part. Consequently all of my old Yes LPs have a little water damage on the top edges of the covers.
I have two in my collection: Cream's Disraeli Gears and Kansas self titled first album (contrary to poster above, the best Kansas album). I love the colors and clothes on the Cream cover; the photo of the band with a storm approaching is pretty awesome on Kansas' debut.  
Just as an interesting aside: Did ya hear how Ahmet Ertegun, president of Atlantic Records, characterized Disraeli Gears when Cream turned in the albums tapes? Psychedelic h*rs*sh*t is what he said! Atlantic released it anyway, and consumers disagreed.