Never before have I ever seen an ISP encouraging people to share their wireless connection before. In exchange, the ISP will provide some additional access to premium services.
They are hoping it will push wireless broadband access, or wi-fi, into suburban and even rural areas. In return for letting other BT customers use part of their broadband connection, anyone signing up to "BT Fon" will have free access to the networks of other British "Foneros" and more than 190,000 Fon-enabled wireless access hotspots across 50 countries including the US, Japan and France.