The Joshua Tree has been U2's most popular album since about ten minutes after it was released. The 1987 smash was the culmination of their American phase, between their florid, young-European phase and their grizzled, mature-European phase. The album's huge commercial success whisked the lads from superstardom to megastardom, and they spent the next decade trying to recover from it — Bono once described the much more adventurous Achtung Baby as "trying to chop down The Joshua Tree."

This deluxe twentieth-anniversary edition (the latest installment in what's becoming U2's annual holiday package) adds a disc of rarities and — if you buy the box set — a DVD. True, the only essential disc is the one you already have, but there are plenty of finds on the B-sides and rarities disc. "Luminous Times (Hold On to Love)" is a longtime goth-blues fan fave that can hold its own with anything on the actual album. "Spanish Eyes" is up there with Madonna's, while other obscurities include "Deep in the Heart" and "Walk to the Water." "Silver and Gold," from the Sun City anti-apartheid benefit album, is a somber yet failed attempt at country blues with Keith Richards and Ron Wood. Wait — where the hell is "Christmas (Baby Please Come Home)" from the Very Special Christmas benefit album? The DVD has the Outside It's America documentary (for extremely serious fans only) and a 1987 Paris concert.

As for the original album, you already know these songs by heart — U2 may have made better albums, more exciting albums and more emotional albums, but they never made a more universally beloved one. There's a lot more Bono than Edge, not to mention a lot more L.A. than Dublin. The songs are U2 at their most abstract, milking the metaphor of Bono's strain to reach the high notes. Yet the best moments connect on a physical level — the glistening bass groove of "With or Without You" and the Hendrix-worship guitar storm of "Bullet the Blue Sky."

“I'm Yours”

Jason Mraz re-emerged after his disappointing second album with this lead single, a Jack Johnson-esque ditty about giving yourself fully to someone else. The success of the reggae-tinged song (it earned two Grammy nods and a spot on the Billboard singles chart for well over a year) was something the folk-pop singer never predicted when he wrote it in 15 minutes at home. "I played a happy-hippie chord progression that would probably work without 50 different Bob Marley songs," he told Rolling Stone. "I thought, 'It's too novelty. This is a nursery rhyme,'" concluding that "you can never guess what's gonna be a hit."