I recently read about a package, which I believe had a name like "tabstat" or "tablestats" which produced a really useful plot of univariate distributions of multiple variables for large datasets. I believe this package was developed by google, but am not sure. I can't seem to find it anywhere (tabstat on google returns a lot of results).
If I'm completely crazy, and this package doesn't exist, what are some good packages for explore really huge datasets? I know plyr has some methods for binning 2D scatterplots to reduce overplotting, but I don't know of any other good packages for visually summarize huge datasets.
There are a number of approaches and packages to solve this type of question, here is one particular approach that may be effective: http://bridgewater.wordpress.com/2011/07/25/91/
You can also find a broader set of distribution presentation options here http://cran.r-project.org/web/views/Distributions.html