interactiveSVG is an R package I made for adding ECMAScript interactions to SVG plots. Flash is the main choice for data visualizations on webpages, but I like the idea of open formats and I think it’s great that you can read the source code of an SVG file.
The package uses the RSVGTipsDevice package that I posted here earlier, and does some scraping and rearranging of the SVG file. ECMAScript onclick events do the work of rearranging SVG elements or updating a text box with a value. I tried animations like easing at first, but noticed that FireFox, Safari and Opera all were pretty slow in rendering these.
Tar file and example SVG files at http://mike-love.net/interactiveSVG/