
Personally, I can't think of another album cover that so accurately reflects the aural journey found within it's sleeve. In this case the white lined radio waves from a pulsar placed on a stark black background create a cold and distant landscape, functioning as the physical embodiment of the music itself. In my mind this image will always be inextricably linked to the music.
Another one that has had a similar impact is the 1990 album "Nowhere" by the band Ride;

This horizon-less watery landscape creates a sense of displacement, with the crest of the wave veering off into some unknown and immeasurable distance. Like much of the early 90's shoe gazing scene, this album was more about textures and landscapes, not promoting any direct meaning but rather providing an engaging sensory experience that takes you to another place with no clear point of reference.
A more recent example of minimalist engagement is the 2002 album by Sigur Rós that is uniquely entitled "( )" (aka the "Parentheses Album");

Sung in the made-up "Hopelandic" language, this dense and ethereal album is one of my favourites from this nameless decade (appropriate indeed). It is at times sublime and beautiful, with some morose undertones thrown in for good measure. The parentheses, filled with black, white and gray images from nature, functions almost as a gateway to another place, inviting you to fill in the blank spaces between.
(Note: The packaging and art work on the CD are fantastic, including blank translucent pages where you can fill in your own interpretations).
With the growing prevalence of digital music I am increasingly interested in the concrete and tangible, and I hope to write more about album art, which for me has always been an integral part of the music that I love. I would also love to hear about the album art that has inspired others and how the visual component relates to the listening experience.