Perhaps a high-power WiFi device is the ticket? Search for SENAO on these forums. Several of us use this adapter and are very happy with it. It's far more powerful than a crappy USB wifi dongle and most PCMCIA wifi cards.Currently I have an USB hub mounted under the trunk, I have hooked up the Microsoft GPS, wireless keyboard receiver and maybe this USB WiFi device if it's better.
Or any other suggestions would be much appreciated.