Until now, fingerprint scanners are used, but not very widely outside of Tom Cruise movies. But a small South Dakota college is doing a trial run of a scanner that has you swipe a finger to make a transaction inside of inserting your plastic credit card into the clot.
The School of Mines and Technology in Rapid City has put the tech into two shops on campus. Purchasers type their birthday into a pad, swipe their finger in a machine, and get a receipt delivered by email. The scanner checks the buyer's unique print to identify him or her, and it also checks for living hemoglobin in the finger, preventing any unsavory characters from trying to use a severed digit.
The 2,400-student campus is filled with only mechanical engineering or hard science majors, which is why they were picked for the pilot program run by Hanscan Indentity Management and one of its subsidiaries, Nexus USA. About 50 students volunteered to try it out.
There are privacy issues involved with these scanners--you have to offer up your fingerprint before it can be identified as you--but it's a give and take. You give your fingerprint, and a thief, presumably, can't impersonate you as easily. Although once these get more widely used, it'll become more worthwhile for someone to figure out how to beat it.
Lets see how far this will go..