This little add-on is to find a free shortcut. Furthermore, it is very useful to learn new shortcuts.
Demo video: https://youtu.be/-PIhDR0RIbQ
Edit by @Brendon Murphy (meta-androcto)
After discussion with @Antonio Vazquez (antoniov) in irc iskeyfree will be added to Blender 2.79 release in the addons "Development" section.
It is a useful tool for discovering hotkeys & both devs & users can benefit from this tool.
What it does is allow the user or dev to immediately search any key combination to check for mapping, contexts & check availability.
A great tool for addons devs to NOT overwrite each others hotkeys & more important, provides a great tool to help redesign keymaps in the future.