I studied the GIS tutorials and reverse-engineered some KML examples to write the KMLGenerator application which produces two and three dimensional overlays on Google Maps and Google Earth. The original request for an application that could render data geographically was for a color overlay, but as I explored the GIS methods I found that extruded features did a better job of conveying magnitude and making memories and so added several additional rendering and color modes.
The app's UI looks like this:
It accepts very easy to understand user-prepared Excel csv files with the location, data categories, and data values and another file I prepared that contains the geocodes for the centroid and perimeter coordinates of geographic entities such as countries and states. It generates output conveying numeric data values in an Earth map that looks like this:
and more of the same in a United States view:
Another project concerned showing street segments where the street is known by a different name in different locations so we could visualize what we were reading in the data. For instance, Pacific Highway South, Aurora Ave, Highway 99, and Evergreen Way are all different names for Washington State Highway 99 between SeaTac and Everett, WA. The map below shows sections of a road that are known by different names using a different color for each different name. A popup provides additional information such as the local street name and the address range.
I wrote this application so it would read and process a large data file and produce a different Google Earth folder for each viewpoint. Doing so allows the person who is reviewing street names for preferred values within a geocode range to run the entire list once and visit the folders, the content of which is one road, as they have time.