Fifty or hundred years from now if the humanity is alive(provided the dangers of nuclear warfare and its accessibility for the evil doers).I think finger print will be the most popular way of buying your groceries.Identity thefts and data hackers will pose serious threats to the credit card companies and banks.So don't be surprised when you visit your nearest super market with your grand-childrens and hear"May I have your finger print?"Instead of "Debit or Credit"?