Luke is behind a majority of every major hit from the past five years, including nearly every chart-topper by the singer Kesha. 
"Timber" features Kesha and Pit Bull singing and rapping over a melody ripped from an obscure but great song by the harmonica player from the '70s group War, called "San Francisco Bay."
But it's been compared by many to a modern-day but far superior "Cotton Eye Joe," the crossover country hit from  the '90s.
Here's the video for "Timber":
As you can tell, the song gets its country flavor — really its entire personality — from the live harmonica playing.
And the guy who played it only made $1,000 bucks on it, according to an interview with the Dallas Morning News' Michael Corcoran:
“When I heard the finished track, I was knocked out,” said Harrington. “Boy, did they turn me up loud.” Harrington received a flat fee of $1,000 for the session. He won’t get any royalties, but he’s hoping the exposure will get him more studio work.