Fingerprint sensors are now everywhere. Once the stuff of science fiction and spy movies, the biometric system now unlocks smartphones, laptops, and credit cards. Yes, credit cards. That is, if MasterCard’s pilot test is successful. The financial services giant has just announced that it has kicked off test in South Africa for a “next generation” card that combines the usual chips you find in cards today with a biometric sensor that promises more secure transactions and less opportunities for fraud.