The first Red Hot + Rio, from 1996, reimagined bossa nova; this one jumps off the politicized, avant-rock Tropicália movement of the Sixties and Seventies. Many songs are classics - like "Baby," envisioned here by arty soul singers Alice Smith and Aloe Blacc, and "O Leãozinho," voiced by Beirut's Zach Condon in his best indie-matinee-idol voice. (Both were written by Tropicália godfather Caetano Veloso, who joins David Byrne for the theremin-charged "Dreamworld.") Other tracks, like the kinetic breakbeat jam "A Cidade," by DJ Dolores with Gogol Bordello's Eugene Hutz, take the Tropicália spirit into the 21st century, where it sounds perfectly at home.

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“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."