For a completely off in left field thought, thinking of serial connections. What about one of those RS-232 to WiFi thiggies? http://serialio.com/products/mobile/wifi/WiSnapAAA.php

If there is some way to get it to work... imagine being in Starbucks with an old Powerbook connected to the WiFi, checking email(slowly) but no frikin' wires WOO! (might be room to hide one inside a portable... maybe one of the imbedded ones on the modem port inside a PB 1XX). 8-o