"I will never get over you/I've still got a lock of your hair," sings Christopher Owens, sounding like someone put a cigarette out on his heart. Owens' ability to turn that kind of longing into killer psych-pop hooks made Girls' 2009 debut so lovable. This EP homes in on a narrow spectrum — songs about loss, loneliness and drug-induced apathy. But Girls build elaborately arranged cuts like "Alright," and they toss in pedal steel and mariachi horns without losing spazzy energy. As the second album looms, it's exciting to hear them sound so bold and articulate.

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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."