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Interesting old patent on verifying credit card numbers via mechanical means

1 pointsby mofosyneover 1 year ago

1 comment

ggmover 1 year ago
If you combine this with the old click-clack card printer, you have offline processing with trust!<p>(trust that its a real card. you don&#x27;t get to know if the gentleman in a red striped shirt with a zorro eye-band is a good person or not, simply carrying a bag labelled &quot;swag&quot;)