Not going far enough, either of you!  Why not make a Skype peripheral, but operating over Bluetooth and not USB?  It wouldn't even need a fancy display.  Let a headset take care of sound and the anwser button, just take care of other input/display tasks.  A commodity display from an <i>old</i> cellphone would do the trick, and these must be dirt cheap by now.  You could probably get the button count down to 6, which is what it is for the Apple Remote.  The components would be dirt cheap.  Margins would probably be very handsome at first.  Make it the size of an old PC card.  It would sell like hotcakes!