Rihanna, Carrie Underwood and Miley Cyrus have joined a superstar cast of fifteen female pop singers to record 'Just Stand Up,' a charity song in support of cancer research. Beyonce, Mariah Carey, Leona Lewis, Fergie, Mary J. Blige and more will also all take part in the fundraising single in conjunction with Stand Up to Cancer, with the goal of encouraging the public to help stop cancer from being a leading cause of death.

'Just Stand Up' will be performed live on Friday, September 5 with a simultaneous broadcast on ABC, CBS and NBC. It will be available as an iTunes download on September 2.

Listen to 'Just Stand Up'!

It's hard to listen to the radio and not hear a song by Rihanna. Whether you're rocking out to 'Umbrella' or her latest hit 'Take a Bow,' chances are you know at least one of her singles by heart. The 20-year-old is everywhere these days -- thanks to her loyal fans -- but do you really know all there is to know about Rihanna? Take this KOL quiz and find out!

When you want to spice up your look, try the hot, new trend of bright-colored shoes. Everyone from Kate Bosworth to Mischa Barton is getting into it!

If you're a streetwear kind of chick, try some cool kicks in bold highlighter hues. If you're more of a girly girl, think about pairing sassy orange pumps with a black dress, like Rihanna did recently in New York City.

Need some more inspiration? Check out Stylelist's tips on how to make this look work for you. You'll be bringing a whole new meaning to "happy feet."

He can bust moves like nobody's business and sing like there's no tomorrow, but besides his "just friends" relationship with Rihanna do you really know anything about Chris Brown?

Check out this 10-question quiz on everything from the 19-year-old's birthday to his pint-sized backup dancers, and let's see how high you rank in fan status!