It's not like we haven't seen Rihanna pretty much nude before, but on the new cover of Rolling Stone magazine she shows a different, um, side of herself.

Wearing a garment that would be better described as a loincloth than a pair of shorts (they seem to have been painted to her derriere) Rihanna reveals just enough "cheek" to send pulses racing -- and offers final proof that she really does have one of the best bodies in the music biz.

SODAHEAD SLIDESHOW: See the sexiest singers.

But Rihanna has serious competition from her even-curvier best pal Katy Perry, not to mention Beyonce and Shakira. And we're not sure how it's possible, but 41-year-old "American Idol" judge Jennifer Lopez just keeps getting hotter. Let us know: Who is the sexiest singer?