In a recent episode of the HBO series Sex and the City, Sarah Jessica Parker's character Carrie Bradshaw signed up to guest model in a fashion show and sashayed down a faux runway in a fabulous Dolce & Gabbana dress.

The $2,500 outfit from D&G's spring 2001 collection stunned Carrie and her fans with its pencil-thin silhouette, satin sheen and gorgeous pattern of dramatic florals. And now, it can be yours. 

The designer dress is among several items from the popular show that HBO has started auctioning off on its Web site. From now until the day after the final episode airs next Sunday, new accessories or dresses from the show will be available every Monday on hbo.com for bidding. Fans have seven days to bid on each item, and proceeds will go to four charities the show's actresses have selected. 

"Over the last couple of years, one of the most common questions that's come up in e-mails or the bulletin board has been, 'How can I get that look? Where can I buy it?' " said Sarah Cotsen, vice president for HBO interactive ventures. "We thought the auction was a great way to do two things — one was to give fans what they want, these unique fashion items, and to connect with charities." 

Since the auction began three weeks ago, hundreds of fans so far have bid on items, including a Stephen Sprouse T that Carrie wore on a lazy morning in bed and a purse with a hip, mosaic pattern Miranda toted to the opening of her ex's bar. HBO's offerings this week are the $448 khaki Coach travel satchel Carrie took to the countryside and a $700 white canvas tote bag that Charlotte recently carried to lunch with her girlfriends. 

Tom Julian, a fashion-trend analyst for New York advertising agency Fallon Worldwide, called the auctions a brilliant marketing move on HBO's part. Since they began, the Sex and the City section of the HBO Web site which also features slide shows of the characters' fashions and lists bars, restaurants and stores in New York that the women frequent has been getting 2,600 hits every Monday. 

"This is really the first show that has gotten the interactive element correct  they're keeping the community factor alive and making the look as important as the characters," Julian said. "I would bet the NBCs of the world are just salivating and wishing they had done this." 

The items that have sold so far have raked in far more than their retail value. A plastic horse-head purse that bobbed around Carrie's waist in the season opener sold for $676 online but only costs $185 at Sex and the City costume designer Patricia Field's Manhattan boutique. And a sequined purse in the shape of an American flag costs $30 at Field's store but sold for $510 on the Web site. The final auction, which begins Aug. 13, will feature one of Carrie's signature horseshoe diamond necklaces by designers Mia and Lizzie. The necklace also is available through Field's boutique for $1,545. 

But experts suggest these items may be valuable in the long-term. 

"The show seems to define, if not a truthful then a mythic, interpretation of the modern American woman," said Dwight Blocker Bowers, a cultural historian at the National Museum of American History. "It tells us a lot about us now and I suspect, when we look back on this generations from now, it will still tell us a lot about how we were. I wish we had a few of these artifacts."

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