Getting and Manipulating Data in R

[DrQ]

RStudio have just released some new packages for reading data into R (faster, seems to be the main claim), but I haven't had time to try them yet.

I'm also looking to update this section of my upcoming GDAT class (Early bird ends in a week, btw). 

Since I also present various visualization tools in R, I would like to know what are your favorite R functions/pkgs for importing and manipulating data in R?

Thanks.