For me it's
Spilt Milk by Jellyfish, which also happens to be the most criminally overlooked album of the decade. Of the 106 Amazon reviews, 96 give it 5 stars. That's an incredible and well-earned ratio.
Power-pop never sounded so filling and substantive at the same time. Honest to Christ, this album is a conceptual masterpiece almost on par with
Sgt. Pepper that really must be listened to as a whole from beginning to end. It deals with a huge range of both subject matter and musical styles and deftly weaves both into a seamless tapestry where this album could have been a feckless mess. The lyrics are pure poetry, painting vivid imagery and profoundly capturing human emotions through brilliant use of language and metaphor. And the studio production is gorgeous -- and I say this as an indie-rock fan who is typically not impressed with gratuitous studio polish. But for once it actually enhances the final product instead of just applying a shine to a musical turd.
And the saddest yet most predictable part? The band imploded after making this album, which was only their second. One wonders if they split because they knew they'd never top this epic. I cannot impress enough upon fans of the old-school power-pop bands such as Queen, ELO, Supertramp, late Beatles, late Beach Boys, and general prog-rock that you should
buy this album right now. I'm not joking.