Ok, so I have read the description about this thing and it seems pretty sweet. However I don't really get it. I'm considering buying it for my macbook pro when i go to college in the fall but how exactly does it work. What type of tv channels would I be able to pick up and I don't have to pay for the service? I know I probably can't get comcast movie channels or anything but I don't really understand what tv stations I would be able to get if I were to use this on campus or at home....Can someone who knows a lot about this or who has one please explain?