Fon founder Martin Varsavsky wants to create a Wi-Fi network with a million hotspots. (By contrast, iPass–currently the largest network–has about 43,500.) He’s got his work cut out for him. Read more in my article for Technology Review, appearing today on the TR home page.

Fon Hopes its Hotspots Will Rival Cellular

Sure, you can browse the Web from your local coffee shop, thanks to its Wi-Fi connection. But what about leaving your cell phone at home and using cafes and other Wi-Fi “hotspots” to place free or cheap Internet-based phone calls using a laptop or Wi-Fi phone? Not yet.

Spanish startup Fon wants to change that predilection for cellular, with a rapidly growing Wi-Fi network owned by its users, rather than a big telecommunications company, and based on shared access. In order to create a large network of hotspots, the company is encouraging network members — mostly, average consumers — to give away Wi-Fi access in exchange for getting free access at other Fon hotspots. Members can use that access, in turn, for Web browsing, e-mail, instant messaging — or Skype-like Internet phone calling.