#20. Flo Rida - "I Cry"

(Photo Credit: Chris McKay/Getty Images for Jingle Ball 2012)

Alicia Keys (Photo Credit: Al Bello/Getty Images)

#18. Taylor Swift - "22"

(Photo Credit: Matt Kent/Getty Images)

#17. justin Timberlake - "Suit & Tie" f/ Jay-Z

(Photo Credit: Dominik Bindl/Getty Images)

#16. P!nk - "Just Give Me A Reason"

(Photo Credit: Scott Barbour/Getty Images)

#15. Krewella - "Alive"

(Photo Credit: Tom Briglia/Getty Images for Revel)

#14. Ne-Yo - "Let Me Love You"

(Photo Credit: Ronald Martinez/ Getty Images)

#13. Maroon 5 - "Daylight"

(Photo Credit: David Becker/Getty Images)

#12. Lumineers - "Ho Hey"

(Photo Credit: Kevork Djansezian/Getty Images)

#11. Ed Sheeran - "The A Team"

(Photo Credit: Dave Kotinsky/Getty Images)

#10. Miguel - "Adorn"

(Photo Credit: Kevork Djansezian/Getty Images)

#9. Bruno Mars - "Locked Out Of Heaven"

(Photo Credit: LEON NEAL/AFP/Getty Images)

#8. Pitbull - "Feel This Moment" f/ Christina Aguilera

(Photo Credit: Theo Wargo/Getty Images)

Scottish electronic musician Calvin Harr

Scottish electronic musician Calvin Harris performs during the second day of the music festival in Hyde Park, Central London on July 5, 2009. AFP PHOTO/Ben Stansall (Photo credit should read BEN STANSALL/AFP/Getty Images)

The 55th Annual GRAMMY Awards - Show

LOS ANGELES, CA - FEBRUARY 10: (L-R) Musicians Ziggy Marley, Bruno Mars, and Rihanna perform onstage at the 55th Annual GRAMMY Awards at Staples Center on February 10, 2013 in Los Angeles, California. (Photo by Kevork Djansezian/Getty Images)

#5. Bruno Mars - "When I Was your Man"

(Photo Credit: Dominik Bindl/Getty Images)

#4. Swedish House Mafia - "Don't You Worry Child"

(Photo Credit: PHILIPP GUELLAND/AFP/Getty Images)

#3. Taylor Swift - "I Knew You Were Trouble"

(Photo Credit: Matt Kent/Getty Images)

#2. Macklemer & Ryan Lewis - "Thrift Shop" f/ Wanz

(Photo Credit: Graham Denholm/Getty Images)

#1. will.i.am - "Scream & Shout" f/ Britney Spears

(Photo Credit: Allen Berezovsky/Getty Images for TRANS4M)