This is an example of a Sankey diagram made using d3.js and the sankey plugin.
A description of how it was put together and techniques for implimenting Sankey diagrams in general with d3.js can be found with the full text in the book D3 Tips and Tricks (for free) from Leanpub.
The data is sourced from the World Resources Institute (http://www.wri.org/chart/world-greenhouse-gas-emissions-2005).
Open in full window for full effect.
This is one of the code samples for the update to the book D3 Tips and Tricks to version 5 of d3.js.