Another reply concerning topographic model:  Sorry to reply to list
but your host came back unknown


This may not be exactly what you're looking for, but for 3-d water
shed models, we've had tremendous success with a company called
EnviroScape
c/o J T & A, inc.
1000 Connecticut Ave
Washington, DC 20036
202-833-3380

sysop@ e2b2.com

They produce a model watershed which is a wonderful hands-on teaching
tool to illustrate point and non-point source pollution, as well as
developing land management solutions.  It is a large, plastic model
that includes rivers, lakes, forest, farms, suburb, construction
site, etc.  They are developing add-on layers for illustrating other
environments, such as wetlands.  It comes with detailed teaching
materials, and, while fairly large (about 4 ft by 4 ft), comes with a
roll-around suitcase.

The company is very *user-friendly* and easy to work with.  They
produce a users newsletter and seem to constantly be trying to
improve their product and address the needs of the users.

Good luck!

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