"People say your brain is like cream cheese/Takes the shape of anything you please," sing Sean Lennon and Charlotte Kemp Muhl on the debut single from their new band. It's a fitting line for a chirpy psych-rocker — one with a whiff of Papa Lennon's surrealist whimsy.

“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."