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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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.
You put your $5 bill on my gold.
And voila! the next american snack food was invented.