On reading about the new Asus N10J, it seems that it allows you to log in using your face:
Smart Technology – Quick Logons through Facial Recognition
Continuing with the tradition of breaking tradition, ASUS introduces a whole new way in which users logon to their computers—through facial recognition. The SmartLogon system detects the user’s face and logs on without any intervention from the user. This system is designed to learn the variations of the user’s facial features, and is capable of performing detection in different lighting conditions.
Maybe I’m a cynic, but I wonder what happens if you take a photo of the target user, print it out life-size and show it to the camera? It might even work with a high-res passport photo scan. Hmmmm, curious…