Britney Spears
The newest X Factor judge has also appeared in shows like Will & Grace and How I Met Your Mother!
Mandy Moore
This singer has arguably had a more successful career since taking up acting. Mandy Moore has landed roles on Entourage, Grey's Anatomy and How I Met Your Mother.
Snoop Dogg
The Bernie Mac Show, The Boondocks, Monk and The L Word are just some of the TV credits you'll find on Snoop Dogg's IMDB page.
Jon Bon Jovi
Apart from being the frontman of Bon Jovi, the crooner has also made appearances on Sex and the City and Ally McBeal.
Gene Simmons
He may spit blood in KISS but when he's not wearing eyeliner—or heels—Gene Simmons has guest starred on Castle, SpongeBob SquarePants, Third Watch and King of the Hill.
Katy Perry
The "Part of Me" singer has graced the stages on Raising Hope and How I Met Your Mother.
Lea Michele
Lea Michele was a broadway star long before she became a diva on Glee, but we're so glad she gave TV a go!
Donnie Wahlberg
Mark Wahlberg's brother, Donnie Wahlberg, currently stars as Danny Regan on Blue Bloods and has been on such shows as Big Apple, Boomtown, The Kill Point and Runaway.
Alanis Morissette
The Grammy Award-winner has starred on such shows as Weeds, Sex and the City, Up All Night and Nip/Tuck.
Billy Ray Cyrus
He's not only been on Hannah Montana with his famous daughter, Miley Cyrus, but Billy Ray has also starred on the CW re-boot of 90210.
LL Cool J
Ladies Love NCIS: Los Angeles!
Adam Levine
The Maroon 5 frontman will make his acting debut on American Horror Story this coming season and we can't wait to see how he ends up scaring us!
Reba McEntire
This country gal had a whole show named after her! Reba, anyone?
Ice T
This legend in the hip-hop community has been on Law & Order: Special Victims Unit for 12 years!
Demi Lovato
Demi Lovato was a TV star long before releasing her debut album, Don't Forget, in 2008, with credits like Barney & Friends, Prison Break and As the Bell Rings. Most recently she starred as Sonny in the TV series Sonny with a Chance.