maps and alternate content

How would one go about providing alternative content for maps?

Yahoo Maps does a good job at providing text directions alongside a visual map.  However, directions from A to B are not the same as an entire map.

Some map alternatives that I know about are:
-Topographic maps with actual rises and falls in the material.  These are expensive, and I don't know that they would provide necessary useful information to a blind user.  And of course, this isn't an electronicly transferable media (tho I could imagine braile displays conveying something like this).

-Descriptions of regions.  These mostly occur in literature - writing them is an art, and I've been able to get very accurate information from them.  But I don't think web developers can be expected to write these.


Thanks for your input,

Benjamin J. Simpson
Education Associate, Web Development Group
NASA Ames Research Center
email: bsimpson@mail.arc.nasa.gov
(650) 604-3292