Even though we have e-banking, we cannot use the bank accounts we manage via e-banking to purchase anything in an online shop. We have to use a credit card instead. That’s a bit strange in the web age.

What about having an url for each bank account? So, the url of my private account may look like daniel.hofstetter.examplebank.com and it would be an OpenID. Instead of providing the credit card data at the check out I would simply provide my bank account OpenID. Then I would get redirected to my account, where I would have to login and to confirm the amount I have to pay. Quite easy (at least on the non-technical side, on the technical side it is more complicated).