What'd you expect, At Folsom Prison? Lil Wayne has released his eighth studio album while still incarcerated on New York's Rikers Island, serving the final weeks of a sentence for attempted criminal possession of a weapon. But gritty jailhouse music this ain't. I Am Not a Human Being, which Wayne cut before leaving for prison, is a party from the start. The record opens with Wayne and Drake dropping raunchy boasts (and STD-themed insults) over a jittery synth-swathed beat. "I am not a human/Shout to all my moon men," Weezy raps. You can lock up Lil Wayne, but his wacked-out spirit remains somewhere way out there in the Milky Way.

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The album has the loose-limbed feel of the rapper's many mixtapes. There are spirited guest appearances by Wayne's Young Money protégés Nicki Minaj and Lil Twist, and beats that range from the power-chord-packed rock rap of the title track to the sultry hip-hop/doo-wop of "With You." In Wayne's patented way, the songs feel tossed-off: He has a gift for making virtuosity sound casual, while delivering laugh-out-loud punch lines every few seconds. He coins a new verb ("Bill Gatin' ") and rhymes "fornicate" with "pajamas say," "pronunciate," "ovulate" and "time of day." You won't hear a funnier record all year. Jailbird or civilian, human or moon man, Lil Wayne is pop's most reliable deliverer of unadulterated fun. He's also the greatest rapper alive.

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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."