Ke$ha and the surprising songs she’s written for other artists

Ke$ha (also known as Kesha Rose Sebert) celebrates her 26th birthday today and while we party in her honour to songs like "Tik Tok," “Your Love Is My Drug” and "C’Mon," let’s take a look at these tunes that were written by the pop singer for other artists.

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“Till The World Ends” by Britney Spears

Rolling Stone and SPIN agree that this Britney Spears “Femme Fatale” album track was one of the best tunes to be released in 2011 and it was written by Ke$ha.

"I didn't get to see [Spears] record the track, but I have met her and she's super sweet,” Ke$ha explained. “She's the queen of pop music, so it was quite a compliment that she wanted to record it. For her to then put it out as a single is f**king amazing. That song was written specifically for Britney - I put my brain in Britney Spears land and wrote that whole song for her."

Ke$ha even appears on “Till the World Ends (The Femme Fatale Remix)" with Nicki Minaj. This isn’t the first time her vocals have been on a Spears tune; she can also be heard on the “Circus” album cut “Lace and Leather.”

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“I just did backgrounds for [Spears] 'cause I was so broke. I needed to pay my rent," she told MTV News. "I got a few bucks. No, [I didn't meet her]. I just did backups for her."

“Disgusting” by Miranda Cosgrove

“iCarly” star Miranda Cosgrove has a Ke$ha-written track called “Disgusting” on her album “Sparks Fly,” but it sounds like it was hard for the songstress to give up the tune to the singer/actress.

“There was a song I wrote for myself and for whatever reason it didn't end up on the record,” she told Digital Spy. “Somebody else really wanted to record it - so I let her, but usually I don't like doing it that way. It was for Miranda Cosgrove."

"The Time of Our Lives" by Miley Cyrus

While she was only paid $1.63 to write "The Time of Our Lives" for Miley Cyrus, it seems as though Ke$ha enjoyed working with the former “Hannah Montana” star.

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“I just write all the time 'cause it's all I can do," she said in an interview with MTV News. "Writing for Miley was fun 'cause I think she's funny. I met her and I liked her vibe, so I was like, 'OK, I'll write, like, a party song for a younger crowd.' ... And that was fun just because I like her."

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