Benetton, American Apparel, and L.e.i have all announced new citizen model ad campaigns.

The most controversial in the bunch is without a doubt the one just launched by US hipster label American Apparel, which is holding a "search for the best bottom in the world." Eager aspiring butt models have already started submitting their behinds, which are free to be rated and commented on by visitors of the brand's website.

"The winners will be flown to LA, photographed and featured online," says AA. The degree of involvement and exposure in the actual ads, however, remains unclear, as "two winners - selected by American Apparel judges - will be eligible to be our next butt model." All finalists will receive $300 worth of the brand's clothes.

Far more innocent in comparison is Benetton's new It's my Time campaign, which will be launched via the Italian label's website next month. Casting for its autumn/winter campaign, Benetton has called on citizen models to submit photos and videos of their personal style and personalities through their site and YouTube. The finalists will be chosen by the public. Submissions need to be made by the end of March.

Fabrica, Benetton's communications center, has also announced that there is another campaign coming up, involving black-and-white digital codes that can be entered on the website for "interactive augmented reality experience." We'll have to wait 'til next month to see what that means.

Finally, a contest open to US fashion fans only: L.e.i jeans (exclusive to Walmart) is also on the lookout for three model citizens to star in its next ad campaign. From February 1 through March 23, candidates can submit photos and videos online or attend one of the casting calls in New York, Miami and Los Angeles. Eligible are all girls aged 15-21, and they will be judged by a panel consisting of Teen Vogue editor-in-chief Amy Astley, designer Rachel Roy, models Chanel Iman and Ali Michael and Allan Ellinger, CEO of Fashion Delivers.