Single-button shortcut for "Do not Disturb"
Sure. Download the ruby script from https://gist.github.com/samnung/c7e767167cf70531ccdc and then just make a bash wrapper to call it.

do_not_disturb.rb on


You'll may want a tool like FastScripts to call the script (and if so, place your bash calling script in ~/Library/Scripts for it to show up there nicely)