Apparently Fujitsu introduced palm vein biometrics (vascular recognition) in Japan in 2004 and this is widely used in ATMs in Japan. Here is an interesting example from one of the early adopters - a Scottish school. The technology is also being used at GMAT test centers. Soon I hope we can dispense with cards and mobile phones for payments and just use our hands. Here is a POS solution from PulseWallet.