All too often we see killer album artwork, only to find it covering a total musical let-down — perhaps banking on the trite notion that people will indeed judge a book, or in this case an album, by its cover.

So we sifted through a sea of mediocrity and sheer hideousness, both graphic and musical, to bring you the most innovative album covers of 2008 — from albums that were actually good. Really, really good.

THE ODD COUPLE

Just like movie sequels, second albums are usually more of a disappoint than an upgrade. Always the non-conformists, electro-pop-hop duo Gnarls Barkley does nothing of the sort. Their second album, The Odd Couple, oozes cinematic beats, powerful vocals and compelling lyrics.

The cover art belies the album’s unique urban sensibility bent through a prism of crisp electronica and vibrant Brit-pop-like undercurrents and an urban sensibility.

Best track: Going On.

19

From the UK’s smoky underground bar scene straight to the soundtrack of just about every American primetime drama, British sensation Adele is just that: a sensation. Amy Winehouse without the substance-induced self-destruction, her powerful raspy voice and infectious melodies stick to your soul like a housefly on melted licorice.

And there’s something to be said for using pure portrait photography in cover art — perhaps because it’s so incredibly difficult to do tastefully, it’s a rarity these days. The few contemporary artists who do it mostly go for an overly Photoshoppy textured and filtered photo, or simply bail with an abstract illustration.

19, however, is supreme in its clean, bold simplicity. The rich negative space and minimalist color scheme yield to the meticulous lighting and the natural curves, building a powerful sense of mystery and allure — a perfect visual metaphor for the music within.

Best track: Right As Rain.

MADE OF BRICKS

Another breath-of-fresh-air British import, Kate Nash burst onto the global scene this year. Made of Bricks vibrates with her perky beats and angst-driven yet profound lyrics, it’s like The Clash was reincarnated in the body of a 23-year-old girl.

The album art captures the Tim Burtonesque magic of Nash’s music — poppy, almost child-like beats and vocals that turn chilling and heavy in a split second under the burden of an adult mind.

Best track: Pumpkin Soup.

SANTOGOLD

The artist who took SXSW by storm and invaded the hipster scene faster than a new American Apparel V-neck did so in good right. Her eponymous debut album is nothing short of brilliant, with a sound so utterly unique that it may just be the stuff of tomorrow’s music history books.

The album artwork, much like the music inside, is a bold manifestation of minimalism with a punch, from the quiet, grainy black-and-white photograph blasted with an unexpected burst of gold, to the provocative layout and muted yet unusual typography.

Best track: Lights Out.

DAVID BYRNE & BRIAN ENO

Yep, we were all over David Byrne and Brian Eno’s latest album, Everything That Happens Will Happen Today — a more-than-worthy compensation for the pair’s 27-year-long absence from the music frontlines.

The cover design itself is both refreshing and nostalgic in that eerie retro-futurism kind of way, complete with slightly-off 3D imagery and an oddly metallic color scheme.

Our favorite track, Strange Overtones, also happens to be a free download on Amazon, so go grab a copy and be your own judge. Yep, it comes with the artwork.

IN RAINBOWS

There was buildup. There was anticipation. There was hype. Which means Radiohead’s In Rainbows had a lot to live up to and could easily disappoint. Except it didn’t.

The artwork itself captures the crisp, high-energy and indulgently vibrant sound of the album in all its organized chaos. Not to mention it inspired arguably even more awesome fan covers and a ton of utterly brilliant motion graphics.

The cover art even inspired an iGoogle spin-off — three artist themes designed by the band and an amazing motion graphics gadget for the House of Cards video.

THE SLIP

Speaking of buildup, no one comes anywhere near Trent Reznor and Nine Inch Nails in that department — we’re talking elaborate secret immersive games, iPhone apps, user-generated music videos, and a very clear message to major labels instructing them to perform anatomically impossible acts.

Their latest “surprise” album, The Slip, was released label-free and without any promotion under a Creative Commons license and despite (or, Trent Reznor may argue, because of) intentionally releasing the album to bit torrents first, it generated tremendous response with over 1.6 million downloads from the official website alone, on top of torrent downloads and CD sales.

And as far as the album artwork goes, the cover image — creepy-cool as it may be — isn’t really the album’s greatest feat. Each song on it actually comes with its own artwork, some alluding to older albums and clearly part of a bigger message for fans to decode.

We have to give it to NIN for extreme originality and innovation across pretty much every facet of the music industry and every fan touch point.

Best track: Discipline.

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