Citibank does my virtual card. The way it works is you apply for your Citibank and their card. When you make an on line purchase with virtual card, it automatically enters a false number to the retailer and then approves the purchase when you tell it to. The retailer gets a fake number, and so does anyone hacking the site.

In fact when you make a purchase, the Citibank automatically see's your about to purchase, it opens the virtual account for you, and even fills out the form for you on the retailers credit card information area of the purchase. Plus you get cash back with every purchase if you like....

From what I understand the number that they generate is only good for one purchase so if anyone attempts to use it after that it is non-valid. I think they generate a new number for each purchase that you make. My banks seem to be interested and are looking into but have not offered this yet.