Yahoo! MapMixer

Yahoo! MapMixer lets you overlay an image file over a map area. Its main use is to match an existing diagram (say a campus map) with Yahoo's dynamic map. A simple two-point identification system lets you align the fixed image (GIF, JPEG, PNG) with a Yahoo map. A Layer Opacity control in the upper right corner lets you control the transparency of the image over the map. You can switch the underlying dynamic map from street map view to satellite view as usual. I was able to fit my graphic image in a few clicks and was navigating through the image layer a minute later. Looks like a very useful and easy-to-use web mapping service.