We repeat the calculation refactoring demonstration from OSCON 2012 and invite viewers to try it themselves.
YOUTUBE L3fcYFQv6S4 Ward shows how to refactor calculations
We recreate the calculation refactoring example from the open source conference and invite viewers to try it themselves.
I demonstrated running, editing and refactoring calculations in my OSCON Talk 
. I created this site so others could try duplicating the changes.