I was reading about key-bindings in Bash. They seem to be based on Emacs but offer the ability to switch to vi based ones.

You can do set -o vi in your .bashrc to effect Bash, but I saw there was also an option to edit a file called .inputrc by adding the following line:

set editing-mode vi

By editing .inputrc instead of .bashrc all programs which use the GNU Readline Library will switch to vi keybindings.

I probably won't switch the bindings as I'm use to the Emacs ones now and I like using defaults, but this fact has gotten me curious about GNU Readline and .inputrc. What popular utilities and programs make use of this library?