Janelle Monáe likes to hover outside categories, with a sound and a look that are both visionary and retro, steeped in OutKast-style hip-hop while hearkening back to Cab Calloway and Fifties doo-wop and James Brown. Her full-length debut — about a robot-populated utopia based on Fritz Lang's classic 1927 film Metropolis — is so ambitious, so freighted with sounds and ideas and allusions, it threatens at times to sink under its own weight. But on ferocious songs like "Come Alive" and the manic neojump blues "Tightrope" (featuring Big Boi), Monáe's charisma and energy are so forceful that the jumble makes perfect sense. Whoever else — whatever else — Janelle Monáe is, she's a star.

“Helen Wheels”

A rollicking good-time hard rocker, "Helen Wheels" was not about a woman but about Paul McCartney's Land Rover, the anthemic chorus voicing the vehicle's reckless joy as "she" took to the road. The song was added to the U.S. version of Band on the Run but was issued only as a single in McCartney's native U.K. "I like that because it's a British road song and there's not many of those around," said McCartney. "It's always Route 66. But Carlisle? How many songs have got Carlisle in them?"