Microsoft's Windows 8.1 operating system gives users the ability to extend a single panoramic background image across dual monitors. Instead of both displays showing the same picture, the image is divided between the two monitors. If using one's own pictures, Microsoft recommends images that are 3,840 pixels wide and 1,200 pixels high. This format works well with most monitors.
To create a wow effect, choose an image where the two halves don't really look very similar. Visitors will then take a bit longer to detect the connection and be more impressed.
A prerequisite for displaying a panoramic image as your desktop background is that both monitors have the same setup - the function isn't available on monitors with different sizes and resolutions.