In Europe and the Rest of the world (don't really know for USA), premium services can be obtained by overcharging SMS, now I wonder to which extent that can be extended to micropayment options on the internet. Walthough... Go to a virtual shop, find something interesting, key in coresponding USN (Unique Shop Number) and that's it! Even if your phone is stolen, the maximum you will lose will be your phone since prepaid cards would have to be purchased anyhow.
Someone must have thought of this before, any clue where I can find more information?