Facebook revealed at the Social Apps Conference that they are currently in the testing phases of a new feature for the social networking site called "Buy With Friends" which is a kind of group buying option. When someone buys a virtual item in an app or game, and posts about it on their news feed, any of their friends will be able to buy the same item directly from that news feed, at a discount. This will allow people to save money on virtual goods, and incitate more people to purchase items. It's a small feature, but that could bring a lot of money if it takes off.