Greenbang is something of a fan of Google Earth. It’s a fun way to go sight-seeing, plan a journey, review a neighbourhood and much more. By making it an open platform, anyone is free to add bespoke layers to the virtual world, such as historical maps (pictured here).
One extra, as highlighted here in earth2tech, is to take an eco-tour of environmental projects (or environmentally damaging projects). Such as this example:
3). Scottish Wind Farms: check it out here Holy Scotland windmills. More info about proposed, in-use and rejected wind power options in the UK country than you could ever want and/or need. Search Google Earth Hacks for wind and check out the many other wind farms out there.