@se7a7n7: Given you would only use this for online purchases, it might not get worn down that much. Plus, they have to guess the order. If you have a system that locks them out/puts a hold on the card after 3 guesses, it could be pretty good.
Well, if you can remember your bank account number, or your ING customer number, you should be fine. This concept is pretty interesting, though it would suck to need to use your credit card in an emergency, and find that your battery finally went out.
@Kaiser-Machead's Cookie-Powered LEGO Machine: I remember my bank account number, and my ING number. But whenever I try to remember another number, I push another one out. Now what was the combo to the safe again?
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I forgot it too...
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