The SIM card ( Subscriber Identity Module) in cell phones provide the same function.

FORBES: Leveraging TPM

The most user-friendly and secure way to enable this is by embedding a SIM card and a communication module inside the car.

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Their latest plan: make the thin, white subscriber identity module (SIM) card inside your phone smaller, Reuters reported Tuesday.

FORBES: Now Apple Wants To Make SIM Cards Smaller, Too

And check this: you can add a WiFi card (as a special Kodak module, which we have a feeling might be CF-based) to it to upload your photos right to the web, or even log in and view your Ofoto pictures on the camera.

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You can also use the same slot to expand the device's capabilities--already Palm has developed a Bluetooth wireless module that fits into the SD card slot.

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