"Justin Timberlake's Cool Fashion Moves" \\ Justin Timberlake \\ Photo:Jason Kempin\WireImage

If you're not familiar with William Rast, you probably will be soon.

That's because it's the name of the fashion line headed by the not-small superstar that is Justin Timberlake. That's right, the "SexyBack" singer.

The 27-year-old singer, actor, restaurant owner, creative muse and face of Givenchy Parfums and designer takes everything on with gusto—and that includes William Rast, the denim-based line he launched three years ago with partner Trace Ayala.

To clear up any notion that WR is just another celebrity-fashion line, the six-time Grammy winner kicked up the fashion notch by creating a collection of cool, contemporary sportswear for men and women that's winning critical raves.

The sharply-dressed Timberlake recently told Vogue: "I naturally gravitate to women who dress unconventionally, sort of like Kate [Moss]—she's captivating to me…Since I was a young, young boy, I always went after the tomboys."

Part of the fashion evolution of William Rast was the result of the recent creative partnership with Johan and Marcella Lindeberg of edgy J.Lindeberg fashion fame. "Johan understood exactly what I was doing a couple of years ago when I started wearing three-piece suits and sneakers—what kind of tip I was on. I said, 'Man—we should partner up,'" Timberlake told Vogue.

Timberlake, who has lately been donning sleek suits and tuxedos, is promoting the WR line himself by starring in a series of fictional trailers shown on www.williamrast.com. In the trailers, Timberlake says, "My name is William Rast and this is my life."

Celebrities are also fans of the WR line—Timberlake's girlfriend, actress Jessica Biel, and singer Jessica Simpson apparently love their WR jeans.

William Rast is sold at Bloomingdale's and higher-end boutiques.