Ashley Greene has donated the gown she wore to the DonateMyDress.org event to be auctioned off in order to raise money to run events to collect and distribute dresses to girls who can’t afford them. The auction says:

Twilight star Ashley Greene — who is the celebrity spokesperson for DonateMyDress.org — wore this amazing alice+olivia gown at Saks Fifth Avenue on Saturday, March 14, 2009!

This XS, sweeping floor-length gown has a trim embellished with beading and stones on top. It has a flattering empire waistline.

Your friends may even recognize this dress from the press coverage of the event, which included The Today Show, Life & Style, In Touch, Seventeen.com, CosmoGirl.com and MyPromStyle.com — and the photos were spread over Twilight fan sites and blogs everywhere.

As a special bonus, the winning bidder will also receive two autographed posters from the event!

Visit the auction page to bid–currently the bid is at $200.