These itty-bitty low power organic transistors can be placed on the surface of bank notes for security or tracking by transmitting information wirelessly to a scanner. A group of German and Japanese scientists manufacture these 250-nanometer-thick transistors using minute amounts of aluminum and gold and a special dry process. They work well on the rough surface of paper and need only three volts to operate.
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You put your $5 bill on my gold.
And voila! the next american snack food was invented.
But really, they will just get damaged too quickly. I don't how much redundancy is built in but if you loose just one or two it may stop working.
Also what about recycling. I know it is an incredibly small volume but it all adds up. Gold is an incredibly important resource. If only we could rapper to stop putting it in their mouths.