Here's how mine works (Score 2)

OK, well, this service has been available on my Mastercard for a few months now. Not that it worked for me; but it's there. Here's how it goes:

You download a strange little Flash program, which sits in the task bar. This program lets you create new credit card accounts. You determine how much the limit on those accounts is, and how long they will last (expiration date). The Flash applet then keeps track of those numbers.

This solves a number of problems talked about here - it keeps track of the numbers for you, and they will last as long as you want (for recurring billing). And, if someone grabs the number, there is a very low limit on how much they can charge from it. You can even drag and drop the number from the applet.

The number is a standard CC#, 16 digits, with check digits. My experience so far has been that the numbers do not authorize very well (that is, I created a number, tried to charge something on it, and it came back as a bad number).

Anyhow, it would be nice if it worked right, because it doesn't need any special new card or other junk, just a computer.