Slingbox or Slingbox HD

I was in Prague a few years back and Saintsabroad was using a Slingbox to let us watch Saints games when they weren't on the European networks. From my understanding, and this could be all wrong, its basically just a link to someone else's cable box and you get whatever channels they can access. So if you are linked to someone in New Mexico, you'd get their channels there in NM.