Sorry I cannot help with the real question.  

However, I think you should look at some of the more creative web sites created by museums.  I think these have significant potential to enrich and broaden the experience of museum visitors, before, during and after.

One which is NOT related to a museum, but which in my humble opinion does much to stimulate curiosity and concern about heritage buildings, is the Fabulous Ruins of Detroit site.

http://www.bhere.com/ruins/home.htm 

I've heard of other good museum sites, and maybe there are people out there with more time to surf the web than me who have some favourite links which do what Cuyler is looking for, but in a virtual sense rather than through reality?

david