Rhanson, I have no Mac experience, but I would think that it should be possible to set things up such that the wifi device (an iPad, perhaps?) and the Mac Mini can communicate with each other without the cable service and the internet (or the cable modem, for that matter) being involved. Either through a router, if your setup includes one and both devices can access it, or directly between the two devices via a wireless "ad hoc network."
Just a thought.
Regards,
-- Al
Just a thought.
Regards,
-- Al