Execute R code online
If the data is public and you want to show off your R skills you can use rpubs directly
You'll need to install the knitr package (v0.5 or later), there is a mini-tutorial just after registration
There is a 'Cloud' version of RStudio, perfect for a quick demo. For more serious work, there is some dedicated plans.

This is a little-known option but it's possible to use R inside GoogleColab
%load_ext rpy2.ipython
Then start your script by
%%R
to execute%%R
x <- 1:10
x
# it should display number from 1 to 10
there is an undocumented feature that allows running R code natively
more info here https://youtu.be/huAWa0bqxtA
I wouldn't rely on it, as it might disappear