Speaking of the airport...

I've got two G4's upstairs, and a Windows PC I want to move downstairs in my apt. Obviously, I don't want to run twisted-pair through the apt to get to this machine. If I got the airport base unit, and installed it upstairs, what would I need downstairs? Would I need another base unit? I'm trying to avoid installing a new card in the Windows machine (it's a Compaq, and they're finnicky bastards), so I'm trying to think in terms of "something that will run off the existing built-in NIC). Of course, if I've got no choice, I've got no choice.

Help from those who've done this before would be spiffy cool.

D