wireless internet question (s)

I know I can get a device that will allow me to use the internet service on my main computer and give me wireless service on the laptop while within range of the transmitter.

But is there a true wireless internet service for laptop users that functions the way a cell phone does ie: able to roam so long as you are within an area covered by the service?

I know there are types that you can use that rely on hotspots but in our rural community those would be few and far between (if there are any here at all)