The major problem with biometric methods of identification is that they are impossible to revoke. Once my fingerprint, under whichever form, is stolen, I can't put it on a worldwide revocation list, as doing so would block both malicious use and my own legitimate use.
Looking at how easy it is to make a false fingerprint or iris image using a standard printer, I have an idea on how to avoid exposing my personnal attributes to the risk of being stolen.
How technically feasible would it be for anyone to make oneself a proxy identificator built on the following basic procedure :
A good quality random generator builds a unique fingerprint mathematical number, in exchange of presentation of multiple proofs of identity and registration of personal secret information. A unique random fingerprint will be generated as the fingerprint image of a private part of a traditional private-public key.
This unique mathematical design is printed on a solid plastic false finger: a proxy finger with a solid ring to fix it on my key ring. This will be used as a fingerprint image of my private key and used in a traditionnal private-public key pair matching authentication.
I use this proxy finger to identify myself in place of my real finger.
In case my proxy-finger get stolen (physically or through any of its stored verification mechanisms), I declare it as revoked through its unique number on a worldwide revocation list.