Ken uses a service from AT&T that allows cell phones in the house to use the existing internet connection to make and receive cell phone calls, even though he lives far out in the country and has almost non-existent cell coverage.
Verizon, T-Mobile, and other cell providers provide similar services.
If you have a cell plan with many minutes you may want to use these minutes instead of paying extra for the long distance service on your land line. If you have an internet broadband connection you should call your cell service provider to see if they have the ability to use your internet connection to route your cell calls while you are at home.
In the case of AT&T, the MicroCell service provides a small box that connects to your internet connection and routes incoming and outgoing cell calls through your internet connection. The device does require a connection to the cell network to initialize itself.
For information on AT&T's service, visit their site here.
Remember to call your cell service provider not your ISP for this service. And when you call tell, them your cell service at home is very poor (if it is) and you may get the service at no additional charge. At one point, AT&T sent out free certificates to many rural customers (that's how Ken got his MicroCell device).