Eighteen Rules: a rule of eighteen calculator

I've launched a new web application written for a friend of mine and any other luthiers and guitarists that might be interested. The application was designed to help guitar makers and luthiers calculate fret distances online using the Rule of 18 [http://liutaiomottola.com/formulae/fret.htm]. You can access the application at "http://humaneguitarist.org/eighteenrules [http://humaneguitarist.org/eighteenrules]" and/or watch the demo video below. ps: the source code and documentation are available here [http://blog.humaneguitarist.org/projects/eighteenrules/]. IFRAME: http://player.vimeo.com/video/72812601 Eighteen Rules: a rule of eighteen calculator [http://vimeo.com/72812601] from nitin arora [http://vimeo.com/user3665532] on Vimeo [https://vimeo.com].