Oh, you mean like Linux does with Device Drivers...
So whereas biometrics might replace a traditional "password" - we need more systems which aren't vulnerable to the type of 1.8-billion-password-stealing-Russian-problems we see all over the place. I have been a big fan of much of the two-factor stuff, and some of the hashing schemes out there. It will be interesting to see what kind of other solutions could exist - though I don't think anything "static" like biometrics gets us anywhere.
I'd include links - but there are a lot of them depending on what you want (Linux, PAM, Apache, Andoird, iOS, etc) - So, "Just Google it!"
You knew the job was dangerous when you took it, Fred. -- Superchicken