99Dresses is e-commerce “crack for women”

99Dresses co-founder Nikki Durkin describes her company as an enabler to one of the world’s most powerful drugs: shopping.

“I have created crack for women,” said Durkin at today’s Y Combinator Demo Day.

The company allows women to upload items of clothing to the website, rate the quality, and then assign prices. But prices aren’t in dollars, they’re in a 99Dresses currency called “buttons.” Buttons can be purchased for a dollar each, and can only be spent on the website. This creates a closed-loop e-commerce environment that the founders hope will feel like a social network.

Thus far, 4,500 dresses have been uploaded to the website.

But how do you constantly monitor the quality of clothing going through the system? Co-founder Peter Delahunty explained to VentureBeat that 99Dresses is really relying on its community. The company encourages users to sign up through Facebook to create a sense of accountability. If a damaged item of clothing does change hands, however, the company will work with that customer to return her money, as well as note the issue in the seller’s history.

Poshmark, a mobile application, provides a similar service to 99Dresses. It also attempts to create a community around selling fashion, but does not have its own currency. Instead, it does this by only allowing people to buy items from “posh parties,” or e-commerce trunk shows that are held around a specific genre of fashion.