Wonder boy designer Christian Siriano just released a new fashion collaboration this week, a maternity line called Fierce Mamas for luxury line Moody Mamas. We were curious to hear about how he went from enfant terrible of Project Runway to designing for expectant moms, plus finds the time to work on a fabulous line of shoes for Payless, and come out with a critically acclaimed fall 2009 line.

We caught up with the busy designer, who was a total sweetheart. He dished with us about the stars he's dressed, how friendly Victoria Beckham is, and what he really thinks about Mariah. He also dropped some exciting hints about new projects he has in the works!

Celeb Fashion Lines

    Celeb: Elisabeth Hasselbeck
    Fashion Line:
    Elisabeth Hasselbeck for Dialogue

    "The View"'s co-host is the latest name to throw her hat in the designer arena with the Elisabeth Hasselbeck for Dialogue line, which will be sold exclusively at QVC. With no piece costing more than $100, everyone can soon be dressing like the perky TV personality.

    Katy Winn, Getty Images

    Celeb: Nicole Richie
    Fashion Line: House of Harlow
    Qualifications: We still aren't sure why Nicole Richie became famous but what's keeping her famous is surely her fashion sense. The fashionista just launched a jewelry line named after 14-month-old baby number one Harlow and if the lines a hit our money is on Richie announcing a junior line named after baby number two (due at the end of the summer)!

    Jean Baptiste Lacroix, WireImage

    Celeb: Lauren Conrad (in her Jade bubble dress)
    Fashion Line:
    Lauren Conrad Collection
    UPDATE: Went out of business on March 23, 2009
    Qualifications: An unfinished stint at L.A.'s Fashion Institute of Design and Merchandising, two years of sorting samples in Teen Vogue's West Coast fashion closet and a new gig with pal Whitney Port at the fashionable PR firm People's Revolution prepped LC for her own designing gig.

    Steve Granitz, WireImage.com

    Celeb: Madonna
    Fashion Line: Madonna for Ed Hardy
    Qualifications: The 50-year-old popstar has long been a fan of Christian Audigier's line and now we hear she'll be making her second foray into fashion design for the label. Madge's first effort (2007's M by Madonna for H&M) was a hit, but it's hard for us to imagine her new creations will be the much needed break from Ed Hardy's unfortunate tattoo cover box.

    Fred Duval, FilmMagic

    Celeb:Taylor Swift
    Fashion Line: L.E.I. Sundresses by Taylor Swift
    Qualifications:The young country singer is releasing a line of frocks this February that her die-hard fans will love and moms can afford. We're sure Swift's brand will expand into denim.

    Charley Gallay, Getty Images

    Celeb: Dita Von Teese
    Fashion Line: Science of Sexy for Wonderbra
    Qualifications: This burlesque bombshell spends most of her time in scanty skivvies, so we're absolutely confident she is capable of creating amazing lingerie! Of her '40s and '50s-inspired line Von Teese says "Underwear isn't just something that you put on for your lover -- you wear it for you."

    Mike Marsland, WireImage

    Celeb: Lauren Bush
    Fashion Line:Lauren Pierce (hits stores in Spring 2009)
    Qualifications: An alum of both Parsons New School for Design in NYC and Central Saint Martins College in London, first niece and former model Lauren Bush definitely has a solid design foundation. Add to that an internship at Zac Posen, a boyfriend with a designer dad (her main squeeze is Ralph Lauren's son) and the success of the popular FEED bags she designed to benefit the U.N.'s World Food Program, and it looks like Ms. Bush has the chops to make her ready-to-wear sustainable fabrics line a hit.

    Astrid Stawiarz, Getty Images

    Celeb: Eva Mendes
    Fashion Line: Vida for Macy's
    Qualifications: Calvin Klein's latest controversial ad campaigns features a naked Eva Mendes rolling around on a bed, so perhaps her new venture isn't really all that surprising. The actress and her boyfriend, film producer George Augusto, are launching a collection of sheets and comforters. While neither has any design background, we're betting the betting the lovebirds know how to make a cozy nest.

    AFP/Getty Images

    Celeb: Mischa Barton
    Fashion Line: Mischa Barton for Stacey Lapidus
    Qualifications:The former O.C. star gets more ink these days for her hair accessories than her acting jobs so maybe this is a brilliant career move: She's coming out with a line of headbands made from a wide array of materials including silk, feathers and crystals, ranging in price from $40-$200.

    Astrid Stawiarz, Getty Images

    Celeb: Janet Jackson
    Fashion Line:Pleasure Principle
    Qualifications:Named after her 1987 hit, the fancy pants (and matching bras) will all retail for under $40. "There's something for every woman, and that's very important to us," Jackson says. "I've always hated when lingerie is uncomfortable, so the fit and comfort was key." Nothing nasty about that, Miss Jackson.

    Arnold Turner, AP