I've got my laptop working in the house with Airport for wireless internet access, but how do I get the empeg into the equation? Do I need another Airport card? Do I put that into the Empeg? Then what?...

Well, you need to get the Empeg onto the wireless network somehow; this thread is a fairly long discussion about the topic, including tips on how to get docked Ethernet in the car. If you have an AirPort base station in your house, chances are good that the Empeg will be able to communicate with it from the car (assuming it's in your driveway or garage, or the like). You can't actually put an AirPort card into an Empeg, but you can plug an adapter into its Ethernet port to allow it to join the wireless network.

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Daniel M. Zimmerman, Caltech Computer Science
Mk.2 #060000058, 36GB
Mk.1 #00101, 10GB