Guy Scott nips into his cubby-hole lab in a far corner of Cross Match Technologies' headquarters--a reclaimed ice-skating rink in Palm Beach Gardens, Fla.--and proudly displays a postage-stamp-size bit of translucent gray film that looks like debris from a darkroom floor. It is the heart of a new machine that he says will revolutionize the global financial system, bring the multibillion identity-theft racket to a halt and make teenagers behave in cars.
The New Zealand--born engineer isn't known as the Mad Kiwi for nothing. But his colleagues and financial backers believe in him. Cross Match, a privately held company, plans...