Desktop Earth is a wallpaper generator. It will generate a high-resolution, accurate representation of the Earth. The imagery is based on NASA's Blue Marble Next and Earth's City Lights. It is a small system tray utility that will automate the process of downloading snapshots of the Earth from NASA, complete with snow, cloud cover, and a host of other configuration options.
Desktop Earth will sit in your systray, run whenever you are logged on, and continuously update your wallpaper with an accurate representation of the Earth. There is no limit on the resolution, and the imagery is calculated from high-resolution 2560x1280 textures, so you can go wild with it even on 30" flat panel displays. Multi-monitor configurations are also supported.