Google Maps & Google Earth have features that could help your lawsuit. We normally think of Google Maps for driving directions, but the street maps could easily be used to diagram an accident. Satellite views may also be available, especially in larger urban areas.
Looking for historic information? Google Earth is a free downloadable program that has archival images back to the 1940s in larger metropolitan areas. This information could be used to show the condition of property, rivers, location of trees, and boundary lines in property disputes.
Wish you had a 3D model of the location in question? If you’re feeling creative you can use Google Earth and Google’s Sketchup tool to create your own 3D visualization. There’s more info on this topic on Morgan Smith’s blog, including links to helpful tutorials.