Using R to install stuff (such as: R, Rtools, RStudio, git, and more!) (installr)
R is great for installing software. Through the ‘installr’ package you can automate the updating of R (on Windows, using updateR()) and install new software. Software installation is initiated through a gui (just run installr()), or through functions such as: install.Rtools(), install.pandoc(), install.git(), and many more. The updateR() command performs the following: finding the latest R version, downloading it, running the installer, deleting the installation file, copy and updating old packages to the new R installation.

Rainbow Plots, Bagplots and Boxplots for Functional Data (rainbow)
Functions and data sets for functional data display and outlier detection.

Create simple packages which pass R CMD check (pkgkitten)
The base R function package.skeleton() is very useful for creating new packages for R. It is also very upsetting as it has been producing the same files which upset R CMD check in the exact same way. And as something terrible happens each time R CMD check barks, this package offers a wrapper function kitten() which leaves an adorable little package behind which does not upset R CMD check .