The U.K.'s Highway Agency is planning to build a wireless network that covers major highways and urban centers throughout the country: The network sounds a bit like Metricom's but in this instance it will use Wi-Fi. The initial plan is to hang 150,000 access points on street lights and traffic lights. The Highway Agency will use the network to monitor cars and offer telematics applications about road conditions. But the network may also be offered to ISPs to service to anyone.
This sounds like quite an ambitious and potentially expensive project for a government agency. If enough people can use the network for Internet access, perhaps those service could help pay off the network for the government.