Kelly slithers in with no shame: Does he actually sing, "It's a party right here hosted by Mr. Sex Addiction"?! Not as fab as the Ke$ha/Nicki Minaj remix (best use of chicken clucks this year!), but not as scene-stealing, either. He's a gentleman.

Listen to "Till The World Ends [Remix]":

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“Youth Knows No Pain”

“Like on 'Youth Knows No Pain' — we are the ones that should demonstrate, because we can take it,” Likke Li said. “We can pierce ourselves, take Ecstasy, dance all night and still go to work at our McDonald's jobs.” Despite the hedonistic sentiment in the song, the Swedish singer also admitted in hindsight her youth had repercussions. “I remember when I was 18-19 and feeling that I know it all,” Li said. “I always feel that I know it all. But that song is about realizing you don’t, and reflecting, ‘Boy, if I only knew what would follow.’”