you could always get wireless card from one of the major carriers like at&t or sprint and just get a monthly data plan and can use it juse like your wireless internet in your home but it will be accessible anyplace you have signal
i'm guessin you plan to hook this up to a laptop
also if you wanted to provide other people your traveling with internet i believe there was a router in the mp3car store that takes PCMCIA cards
then you'd be able to use the wireless feature on your laptop if you have one
i think there might be some PCMCIA to usb convertors out there