Any one knows a tool to find difference between 2 notebooks at the source level?

The compare notebooks tool in workbench 2 seems to work at the internal data structure level which is not useful for me. I am looking for tool that looks at differences at the source level (what one sees when looking at a notebook, i.e. not the FullForm).

I am using V8 of Mathematica on windows.

EDIT1:

How I display the output/report from NotebookDiff in a more readable form?

![enter image description here](https://i.stack.imgur.com/CvwC3.png)