Simian (Similarity Anlyzer)
Finally I had time to test drive a tool that was sitting in my tools bag called Simian (Similarity Analyzer) that is responsible for identifies duplication in Java, C#, C, C++, COBOL, Ruby, JSP, ASP, HTML, XML, Visual Basic, Groovy source code and even plain text files.
I ran it (with no special exclusion) using the following command line:
Simian.exe -includes=**/*.cs -formatter=xml:simian.xml
Which actually iterate on all C# files recursively. I would suggest to exclude relevant files to reduce noise (E.g. Dynamic content like designer...).
After few SECONDS It found more than 1000 lines of code that are duplicates on an old project I had laying(pretty big).
Needless to say I was shocked, so I checked part of the files and I actually found pretty basic things that were copied as part of unit tests and parameter tests.