Got used in finding RFIDs in products at the supermarket ? check this out.

"Japan school kids to be tagged with RFID chips
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The tags will be read by readers installed in school gates and other key locations to track the kids' movements.
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The chips will be put onto kids' schoolbags, name tags or clothing in one Wakayama prefecture school. Denmark's Legoland introduced a similar scheme last month to stop young children going astray."

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