In 2005, Madonna was coming off of her political state-of-the-world album American Life. She was looking inward on the follow-up but also feeling her club music roots. That album, Confessions on a Dance Floor, had a big late '70s/early '80s feel to it and the first single, "Hung Up," even sampled ABBA's "Gimme! Gimme! Gimme! (A Man After Midnight)."

"People don't usually think of dance music as having substance," Madonna mused. "Dance music is not usually about anything. I like the idea of revealing things about myself. The best songs do reveal certain aspects of whoever wrote that song and I like the idea of doing that with dance music, and putting those two [things] together."

These days, Madonna has been revealing a bit more about herself in interviews (including one where she shared her feelings on the Catholic Church and another where she shared her thoughts on feminism). She's, of course, been promoting her latest album, Rebel Heart.