John links to an absolutely brilliant prouct from Microsoft. The great thing is some of the products that are coming out next year. A fingerprint reader that is integrated into the mouse. This will probably take biometric technology mainstream.
My iPAQ has had a biometric login capability for years and its very convienient. What they will need to watch out for is that no input device (particularly a hybrid like a mouse) allows the finger print to be read whilst the hand is in the resting position, otherwise someone will figure out a way to rip the fingerprint from the device and re-use it in other places – although I am sure there are probably protections in the API to stop this.