Open Data, Open Standards & Open Source
Independently, they're changing the world. Together, they're even more amazing. For example...
Example #1: USGS earthquake data
The map shows earthquake locations for the last week; the lower plot shows earthquake magnitudes during that time period. That's cool, but it's not amazing -- USGS has been providing this kind of real time data stream for years.
What's amazing is that you can use your browser to analyze the data. Try it. First, run your mouse along the lower plot to filter the data displayed on the map. After you create a filter pane, you can also move it around with your mouse. Once you get the hang of it, you can quickly drill down into the data to geolocate the largest earthquakes, or smallest, or most recent, etc.
This example only begins to demonstrate power of D3. And the demo became remarkably easy to create when USGS upgraded their real-time data feeds to conform to the GeoJSON and JSON open standards for data exchange.