Adam Buenz has been working on a very cool authentication method for SharePoint: BioPoint - The Biometrics for SharePoint! Although I'm not sure in how many scenario's this authentication method will be used, I really like the approach of this very cool project.
"Because this is the only device I have available, what will be introduced during the duration of this post should work with anything that adheres to the Precise BioMatch™ criterion. The same paradigm could be applied to other Biometrics, but the Precise Biometrics was the only API that was applicable to my current experiment."
Read the complete "how to" article here.