If you get a new passport any time soon, you might discover that the newer issue has an RFID chip.

RFID stands for radio frequency identification. Big retailers like Wal-Mart use them to track inventory.

They're basically tiny radio receivers and transmitters that can store, send, and receive information. For example, Wal-Mart can put an RFID chip on a pallet of merchandise that has information about how much stuff is on the pallet, where it is in the warehouse, and so on.

Once the chips become small enough, companies could put them in every item they sell to keep track of exactly what's being bought, where, when, everything.

If you buy a pair of shoes with a chip inside, the store gets information about your buying habits. The thing is that the chips keep working even after you leave the store, so, at least theoretically, anyone with the right technology could read the information on the chip.

It wouldn't be too bad if some stranger knew how much you paid for a pair of shoes or where you bought them, but a chip in your passport might be a whole different story. If you're traveling in a foreign country and someone with a scanner wants to find out where you're from and who you are all they'd have to do is read the chip.