What USB wireless adapters are compatible with Mac 10.4? What about the linksys USB adapter? If you plug it in does it get regognized by the system and use the airport icon? Or does it have seperate software? Or does it even work?
I don't know about Linksys specifically but most of them require drivers. This is one area where I really wouldn't go. USB wireless adaptors are notorious for wrecking your OS when it comes time to update or even, if you're unlucky, as soon as you plug it in. They're all terribly supported and incredibly unstable so, if possible, get the appropriate AirPort (or Extreme) card for your machine and save yourself the heartache.