Paul mentioned this (http://www.robichaux.net/blog/2007/01/turn_your_car_into_a_wifi_hotspot.php) and it has to be the potential gadget of the year!
The first Internet service provider specifically designed for cars. Fasten your seatbelt. Because the driving experience will never be the same again. With Autonet Mobile, the first ever, always-on mobile broadband network, you and your passengers can now enjoy internet services and Wi-Fi connectivity whenever you want to by turning your car into a Wi-Fi hotspot on wheels. IM, chat, stream media, email, game on-line, listen to music and more.