Here is a Nifty Open Interest Tracker blog with following features
Nifty OI Tracker Contains Open Interest Data in Barchart format.
Auto Update at EOD
Computes the PCR Ratio(Put call ratio)
Computes the SMR Ratio(Smart Money Ratio)
Inorder to use this widget on your blog
Copy the html code and paste this in your blog to get the Auto Updated Nifty OI Tracker Widget.