I checked inside my G4 PowerMac to confirm the little pigtail with a 90 connector that’s plugged into my Airport Extreme (802.11g) card.
My plan is to build a high gain cantenna, connect it to my powermac instead of the existing Omnidirectional internal antenna, and use it to feed a focused beam to the Airport Express downstair on my stereo.
See Pepperidge Farm Cookie Cantenna with a 15-18dB gain!

So I checked my old ham junkbox yesterday and found a bulkhead N connector – I got a can of Pepperidge Farm Pirouette cookies when I did the groceries today – and I ordered a 60″ pigtail (MC-Card connector to N) a few moments ago! About $30 for the pieces (mostly the pigtail). I’ll make a little mount from an old gooseneck microphone stand. With any luck I’ll get the pieces late next week and maybe get a chance to try all this out in the next couple weeks.

Lotta work for an automated (computer) radio station …!