Metacarta is a really cool technology that parses natural language documents for geographic locations. Think searching documents and webpages for words like:
"Today in Royal Oak a new business..."
where Metacarta can then pull out Royal Oak and try and continue searching the documentation for more location pertinent information that Royal Oak may be in Michigan, or Florida, or Australia, or wherever.
The examples use the OpenLayers, mapping agnostic, webmap tool.
For a great example of all these technologies, check out Gutenkarte, which maps the locations for any book found in the Project Gutenberg library. I wonder how it deals with imaginary places, and mixtures of real and imaginary places (like Nowhereville, NY)