UCL Centre for Advanced Spatial Analysis:
"The Google Map Image Cutter is an application designed to take any image or digital photo and cut it into tiles which are displayed on a Google Map. Using this tool, large images can be published on the web in a format that allows the user to pan and zoom using the standard Google Maps interface. Although publishing large digital photos is the most obvious application, this technique can also be used for annotated maps of an area that are not to scale e.g. directions for how to get to the office."