In the wake of the attack on Sony's PlayStation Network, lots of people will be cancelling their credit cards. Just in case. That won't cost Sony a cent, but boy will it cost the banks.
It's estimated that, with the little slivers of plastic costing banks $3-$5 to replace, if large numbers of PlayStation Network account holders do the safe thing and cancel their cards it could cost international banks up to $300 million.
There will also be money lost while cards are being replaced as, without cards, the bank's customers won't be buying anything on them, hitting their back pockets even more.
Not that this will upset any of you, since these are banks we're talking about. Indeed, I'd imagine it may - red tape aside - convince more of you to cancel than would have otherwise been the case!