IBM / Lenovo has been implementing biometrics in the form of fingerprint readers. Currently they are including fingerprint readers on models within the:
I have been using the fingerprint reader on my X41 Tablet and T43 Notebook. It is incredibly functional, easy to setup and secure. It is easier to enforce security rules. For instance, computer locking after only a few minutes of inactivity is less of a burden. On the tablet it is incredibly useful. Entering a complex password would be difficult with the digitizer, the fingerprint scanner allows me to maintain a complex password.