You can download my JavaScript-based D'ni calculator from this location:
http://www.riedl.org/calculator/calculator.zip
You may host this archive on any D'ni-related website if you like.
Feel free to use this script in order to code a better calculator, as long as you keep my name somewhere.
Mac users should check out the D'ni calculator dashboard widget (download page) by Matthew Harper. He gave my calculator a great new look by renewing the graphics and putting it into a widget framework.
Happy calculating!
Simon Riedl