Wifi that stretches for miles

Helium provides a communication network using hotspots that people install in their homes.
As a hotspot owner you earn helium tokens – a cryptocurrency – for providing coverage.
There are now about 5,000 hotspots in the world, providing full coverage in most major US cities.
So far, the Helium network has been used for tagging/tracking devices and also smart water meters, among other applications.