On Jul 19, 2011, at 7:07 AM, Neal Becker wrote:

> I go to quit emacs, or kill a buffer.  It has been modified.  How can I see what 
> the changes are?  An ediff for this would be nice.
> 
> You know what would be great?  If when asking whether to save the buffer, emacs 
> would offer to show the diff.

I like your suggestion.

What I do is "undo" which tends to remind me what / where the buffer got changed.  Often it was by accident.  And if I want to keep the changes, I redo and then save.