Google Earth is, essentially, a globe sitting in your PC - and an interactive one at that. Give it your postcode, and it will take you on the journey from space to your own back yard.
You have to download software and there are some exacting requirements to use the full 3D effects, so to run it you need Windows 2000, Windows XP or Mac OSX. However, all requirements are explained on the download page in a clear fashion. There are also paid-for upgrades that will give you GPS device support. Once you've downloaded the software, you start in space zooming rapidly towards Earth. You can then click and zoom on to virtually any part of the planet to get a close up. Search by address or just browse around.
It uses stills from satellites and pictures taken from aircraft in the last three years to make a giant collage. They are static but updated regularly. It mainly covers the US, Canada, UK and Western Europe, but I could even find the exact house where I am moving to in Australia. You can add layers to look at fine detail like schools, parks, hotels, airports so it's useful for planning trips or looking for a home.
- Dr Palmer is a GP in Fareham, Hampshire.