Biometrics for identification

> Are there security schemes or proposals that assume other people don't 
know my fingerprints?

Have you never seen someone who unlocks his or her laptop with a 
fingerprint reader (and no password, i.e. one-factor authentication)? I 
bet that they think this is secure because their fingerprint is just like 
a password. Otherwise it is pretty worthless against semi-interested 
attackers.

I am starting to wonder how many laptops don't have the owner's 
fingerprints right there, on their surface...