Call it the Rihanna effect. For December, bubbly Kate Hudson tries living on the edge for Elle UK and sweet Natalie Portman mimics Cameron Diaz's fierce V cover right down to the suggestive open mouth. Then there's classy Nicole Kidman looking like—and talking about—sex in British GQ.

The most ironic part is that real-life edgy actress Kristen Stewart has transformed into a sensual, high-fashion glam goddess for Harper's Bazaar.

Or is it that ironic?

Nicole and Kate are currently promoting their upcoming burlesque musical, Nine, which explains this and this. Natalie wants to be taken seriously, so her girlie-girl image just doesn't cut it. And as much of a tomboy as Kristen tries to be in her own life, she's a soft beauty in Twilight, and New Moon is just around the corner. So let's skip Kate, Nicole and Natalie this time around and just enjoy the stunning editorial the normally grungy Kristen did with Robert Pattinson…

Even funny gals like Tina Fey like to get dolled up now and then.

The 30 Rock star visited The Late Show with David Letterman last night and dished all about going glam for next month's Harper's Bazaar.

"They put these long, long hair extensions, that's mostly wig, on me," she said of her cover shoot. "And when they put all the fans on you, the wind machine, the lights and all the gay magic you start thinking like, 'Yeah, I look like this!"

Of course, when the wind stopped, Tina said she returned to her normal "homely" self. But we think she looks pretty fab without the "gay magic." And right on trend, too!

Keep reading to see the comedienne's au courant polka-dot ensemble—and to hear the virginity hilarity that made us forget all about Letterman's sex scandal.