We had talked in a little bit of detail about biometric security in the past, but this quick CNET video was just too cool/interesting not to post.
Traditionally, we think of biometric security as fingerprint authorizations or retina scans, but security based on physical attributes are a) difficult to implement because the physical infrastructure is not there (does your laptop have a retina scanner?) and b) insecure because you can't change your fingerprints if a hacker does somehow get your biometric information.
Keystroke authentication, as far as we can tell, is by far the most likely form of biometrics to be employed on a large scale because it works on two levels — the password and the typing patterns. If one is compromised, the other can be easily changed.