Biometric technology was once the stuff of sci-fi—how many movies show someone having their hand or eye scanned to get entry into a secured facility? But today biometric tech can be found in millions of people’s pockets—as the fingerprint scanner on an iPhone.

Of course, fingerprint scanning isn’t foolproof. Hackers have stolen fingerprints from photos, and used fake prints to fool Apple’s touch ID. Plus, there’s always the brute force method, like the time a gang in Malaysia cut off a guy’s fingertip—with a machete—to interface with the fingerprint-recognition system on the victim’s Mercedes. Read more