Harvey Bingham found this article by Mark Tosczak on Wired News:
Jason Morris uses a trackball to move a cursor across a map of ancient Britain dotted with Roman forts and cities. As he passes over a location, a speech synthesizer pronounces the name -- and will spell it, too, as sometimes the computer's Latin pronunciation isn't up to snuff.
When the cursor passes over land, the sound of horses galloping comes from the computer's speakers. Move it over water and the sound of waves breaking on a beach emanates.
Full story [wired.com]