There are a total of four USB ports (one on the front) which comes in handy for external drives and maybe even accessories down the road -- althoug not surprisingly, the Logitech USB camera for the Revue doesn't work with the Sony.

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Teusink cracked open a Logitech R-R001 presenter device and the USB dongle that allows it to communicate wirelessly with a PC.

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If cost is a concern, I recommend the Logitech Wingman Attack, which did not cause any problems on my system (and is not USB).

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