From Nokia: "Green Explorer works with its partners to provide sustainable tips and advice on how to live green and travel clean. You can share your experiences and ideas here and help make a world of difference. The service is designed to help you decide where to go, how to get there and what to do when you’re there. The idea pushes the environmental aspect by trying to provide small solutions and actions which when combined have a greater impact on the environment."
Green Explorer is to be found here and, although the accompanying widget is claimed to only be for the 5630 XpressMusic and N96, it should also work fine on other Web Runtime-enabled S60 smartphones (i.e. anything recent and patched up to date). Note that the widget isn't integrated into Nokia's Account system yet, so you'll have to create a new login. Comments welcome.