The latest addition to the site is the Flash Specifications Comparison
Use this tool to compare any recent Canon flash model to any other recent Canon flash model. Use the comparisons to assist your purchase decision-making process. Share flash comparisons with your friends and forums. Or just compare flashes for the fun of it.
For a specific example, I'll preload a comparison that I am looking at right now: the Canon Speedlite 600EX-RT Flash compared to the Canon Speedlite 580EX II Flash
You will find a link to this tool under the "Tools" menu option, on the Tools
page and in the individual Flash Reviews
As always, let us know if you see any errors/omissions or have ideas for improving the tool.