Some modern notebooks come with facial recognition. A face being something you have, of course. This can be paired with a Windows password (what you know) for two-factor security.
This is not strong two factor security as facial recognition, at least as currently implemented, is susceptible to a wide range of attacks. A presentation at Blackhat covered these vulnerabilities in detail.
J Wolfgang Goerlich
YouTube – Face Recognition Commercial Lenovo
http://www.youtube.com/watch?v=H2a0KYtG97E
BlackHat: Your face is NOT your password
- http://www.blackhat.com/presentations/bh-dc-09/Nguyen/BlackHat-DC-09-Nguyen-Face-not-your-password.pdf
- http://blackhat.com/presentations/bh-dc-09/Nguyen/BlackHat-DC-09-Nguyen-Face-not-your-password-slides.pdf