A set of functions, some subset of which I use in every .R file I write. Examples are table2(), which adds useful functionalities to base table (sorting, built-in proportion argument, etc.); lyx.xtable(), which converts xtable() output to a format more easily copy-pasted into LyX; pdf2(), which writes a plot to file while also displaying it in the RStudio plot window; and abbr_to_colClass(), which is a much more concise way of feeding many types to a colClass argument in a data reader.
Having tired of constantly declaring a bunch of the same functions at the head of my code over and over, I've finally embraced the build-your-own-package approach to manage all of these functions in a more modular & less verbose way.
Feel free to poke around & pick and choose these functions for your own use. It's hard for me to call them mine since most of them are the direct result of something that came out of StackOverflow anyway.
I doubt anyone is reading this, but if so, please feel free to give feedback or offer your own notes on functions you use constantly that smooth your R coding experience.
PS For now, this package is not on CRAN.