In the middle of his 2010 concerts, Tom Petty interrupted the hits for a stretch of electric R&B and psychedelic jangle from his rebirth record, Mojo. This vinyl LP, issued for Record Store Day, is a crackling facsimile of the minisets inside those shows, including the tough freestyle strut "Takin’ My Time," the hard-blues-and-rave-up combo "I Should Have Known It" and the Allman Brothers-with-acid waltz "First Flash of Freedom." There is one non-Mojo nugget: a 1999 B side, "Sweet William," which suggests Bob Dylan's "Ballad of a Thin Man" juiced with the garage-rock helter-skelter of Count Five’s 1966 hit "Psychotic Reaction."

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“IRM”

Fashioned to mimic the sound of a magnetic resonance imaging or MRI, "IRM" (the French designation for the brain scan) grew out of Gainsbourg’s love of the sound of the clickety-clack of medical machinery. The IRM album project also marked the fulfillment of two goals for the singer: to document a traumatic experience, and to record an album with Beck. Though her co-creator and producer didn’t necessarily know the details of her water-skiing accident and resulting cerebral hemorrhage (which lead to the IRM of the song's title), he somehow knew how to handle the material. "Beck had a way of guessing what I was thinking and feeling without me telling him," said Gainsbourg. "We never discussed these things explicitly."