Lady Gaga's Barney's Workshop, Rihanna's Collection, Janet Jackson's New Line And More

.On Monday evening, hordes of fans watched Lady Gaga grace Madison Avenue's Barneys flagship store in a custom Chael Eliza Doolittle-worthy dress, hoop-skirt and all. The occasion: a ribbon-cutting ceremony for her outlandish Workshop, which opened its doors at 11:59pm.  As you might expect, it was a scene that drew a rambunctious collective of determined young fans, infamous transvestites, fashion personalities, and celebrities from different parts of the pop cultural map. Nicola Formichetti, Blake Lively, Alan Cumming, and designers Prabal Gurung and Alexander Wang all came out to shop Gaga's wonky wares early, including our new workshop item of choice: the Linda Farrow Mickey Mouse shades, of "Paparazzi" fame, retailing for $425.

. Viewers shocked by Rihanna's profane shoes won't be thrilled to learn this, but she has designed some outfits for Armani, making December a particularly prolific fashion month for the singer. As her second fragrance, Rebelle, hits stores next week,  her capsule Armani Jeans collection also goes to retail at select vendors. Among the looks: some basic tees, two pairs of jeans, a leather biker jacket, a purse, and some lingerie open to wardrobe intepretation.

. Janet Jackson has quietly served as the face of Blackglama's fashion label for a few seasons, but she's ready to step up her role, collaborating with them on a 15-piece line of winterwear that's set to hit stores this month. Saks Fifth Avenue and Bloomingdale's will carry the line, which offers the pop diva's spin on coats, vests, jackets, scarves, and gloves, all accented with the brand's signature mink – and leather, if you're nasty.

. Replicas of Bella Swan's famous wedding dress went up for sale the day after Twilight: Breaking Dawn, Part 1 broke records at the box office. Kristin Stewart's original dress was created by legendary designer Carolina Herrera, while the replica is sold by bridal retailer Alfred Angelo for $799. The same company has also produced replicas of Elizabeth Taylor's wedding gown in 1950's Father Of The Bride.