CSHTMLDiff Control 

CSHTMLDiff Control is a powerful ActiveX control which allows you to compare two revisions of a file visually in a quick, easy and friendly way. CSHTMLDiff utilizes a robust engine that recognizes various file types, including Text, XML and HTML.
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CS-RCS Pro 

Professional version control and software configuration management for Windows. Fully integrated with Windows Explorer and provides the most powerful and intuitive solution on the market today. Free for single users and open-source developers.
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