Facedeals may still only be in its trial period, but the Foursquare-like deals program that uses facial-recognition software to check you in on Facebook when you enter participating businessed is sure to incite all manner of responses when it's rolled out for the general user.
Relying on the preauthorization of its proprietary app via your Facebook profile, Facedeals maps the current physical appearance of your face by scanning your most recently tagged photos. When you enter a participating business, a custom-developed Facedeals camera will scan your face and automatically check you in. Then Facedeals will send personalized deals and discounts, based on your Facebook "like" history, directly to your smartphone.
The standalone Facedeals cameras have been developed around open source—including Raspberry Pi, Arduino, OpenCV, and the Facebook Graph API—and can be configured remotely and require only a standard 110 volt wall outlet and a wifi connection.