library(ggplot2)
library(gridSVG)
qplot(disp, mpg, data=mtcars) + facet_wrap(~ cyl)
grobs <- grid.ls()
names <- grobs$name[grobs$type == "grobListing"]
for (i in unique(names)) {
    grid.garnish(i, 
                 onmouseover=paste("showTooltip(evt, '", i, "')"),
                 onmouseout="hideTooltip()")
}
grid.script(filename="tooltip.js")
gridToSVG("qplotbrowser.svg")