If you get a wireless router.. such as a DWL-900AP+, you can set up a wireless PCMCIA card in the laptop and surf from the wireless router. And most of those routers come with dual antennas, so that you can do a vertical and horizontal polarization, so that you can surf from the whole house.. different floors and all.
So you'd spend about $150 for the router, and about $60 for a Wireless PCMCIA card.. and you could just plug the PC into the router with Cat5 cable.