30. “Rock Me In”
A playful Circus bonus track with one of Spears’ most groovy choruses. “Rock Me In” has fewer sharp edges than the rest of her 2008 album, and would have suited the star’s Austin Powers cameo perfectly.

29. “Unusual You”
A woozy, melodic departure from the bustle of Circus. After enduring nearly three years of nonstop media scrutiny as her personal life crumbled, Spears sounds earnestly relieved to find someone who isn’t breaking her heart in song, at least

28. “Mona Lisa”
“She’s the original / She’s unforgettable,” Spears sings on a 2005 track from her Britney & Kevin: Chaotic EP. This is the sound of Britney’s brain when she decided it’d be a good idea to introduce the world to Kevin Federline via reality show. So, in short, amazing.

27. “Don’t Keep Me Waiting”
Travis Barker provides the booming beat on this Femme Fatale bonus track, which sounds blissfully organic, loose, and fresh next to the tightly wound synth-pop on the rest of the disc.

26. “Womanizer”
Spears’ first single that could legitimately be called a “comeback” track paired slicing synths with a stuttering chorus. There isn’t much to the melody, but it’s more than worth it to hear Britney winkingly sing, “You say I’m crazy? I got your crazy.” 额马戏三连

25. “Early Mornin’ “
Moby contributed this flute loop head-nodder to In the Zone. His rippling production more than makes up for the fact that Brit spends most of the track yawning and giggling.

24. “Do Somethin’ “
A single from 2005’s Greatest Hits: My Prerogative that’s 100 percent pure swagger

23. “Get Naked (I Got a Plan)”
The weirdest, dirtiest, grimiest song on Blackout. Freakier than “Freak Show”!

22. “I’m Not a Girl, Not Yet a Woman”
Worth its weight in Cheetos for providing the punch line to a billion Britney one-liners, this Dido-written ballad from Britney is grade A schmaltz.

21. “Break the Ice”
Spears shakes the paparazzi long enough to get to a rave.

20. “Boys”
One of the Neptunes’ magical collaborations with the Princess of Pop ââ,¬” a Chic bass line, bare-bones beat, and three and a half minutes of Spears cooing about those nasty boys.

19. “Why Should I Be Sad”
An almost literal narration of Spears’ failed relationship with Kevin Federline fed through Pharrell Williams’ suave filter. The only ballad on Blackout caps the album with a defiant question nobody was expecting to hear from Britney’s lips.