Large retailers like WalMart, Target and Costco are investigating the benefits of using biometrics for customer payments. One of these days soon, you may be able to pay at the checkout counter by inserting a finger into a fingerprint reader, circumventing the need to write a check or carry a credit/debit card around with you (any of which could be lost).
Some people see it as an invasion of privacy, while others see it as a way to thwart identity thieves and other fraudsters. For the retailers, transaction costs can be reduced. We can only hope they might pass some of the savings on to us, the customers. Read more about it here.