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RFID chips are "radio frequency ID" chips. They are very cheap, and are embedded in many of the products you buy at Walmart. They are used by Walmart to reduce shoplifting. Unfortunately, they also reduce privacy. However, this problem is (technically) easily solved. All we have to do is demand that Walmart transfer control of the RFID chip inside a product we buy to us when we pay for the product.
More to come.