http://steamcommunity.com/auction
So It seems Valve has created a new way to make people do silly things with their items. The idea of the Steam Holiday Auction is to take Steam items, such as cards, emoticons, and backgrounds and convert them into gems which you then use to bid on games.
Personally I think it is quite silly, as the Steam Holiday sale is just around the corner so why not buy games then? The floor is now open to discussion.