I hope this is the right place to share this.
FlashBuilder/Eclipse has a shortcut to duplicate the line(s) you’re on, either above or below the caret, and it’s the editor feature I’ve missed most since making the switch to Unity, so I replicated it in a little MonoDevelop plug-in: http://philippseifried.com/blog/2012/11/09/monodevelop-duplicate-selection/
Works on Windows and Mac.
