Amazon unveiled plans for the new "Amazon One" machine yesterday, a contactless card reader that accesses your payment information through just a wave of your hand. Users will insert their credit card and then hover their palms over the device in order to link the payment mechanism with their palm signatures. Once the card is on file, you'll be able to enter the store in the future just by holding your palm over the device for 1-2 seconds. Amazon stresses that the device is contactless, w...