I'm writing (possibly) a small document management system. Technology of choice is ASP MVC. I'm looking for api/framework to compare MS Office documents (Word, Excel). I have found this:
groupdocs - it's exactly what I was looking for but prices are killing me.
Other options I have founds are stand alone applications, one of which is not perfect but could do the job. comparesuite - it has silent command line mode that can generate HTML diff report.