using just out odf the box features, I would run a search for files names *.* to get a list of all of the files in the vault. then open it it excel and do the sorting and checking there.
You could run a query against the database...
Select D.DocumentID, D.FileName AS [File Name], P.Path AS [Project Path], S.Name AS [Current State]
From Documents AS D
INNER JOIN DocumentsInProjects AS DIP ON D.DocumentID = DIP.DocumentID
INNER JOIN Status AS S ON S.StatusID = D.CurrentStatusID
FULL OUTER JOIN Projects P ON DIP.ProjectID = P.ProjectID
WHERE D.Filename IN (Select Filename FROM Documents Where Deleted = 0
GROUP BY Filename
HAVING (COUNT (Filename) > 1))
ORDER BY D.Filename
Try Duplicate Files Deleter as it can remove any problems that you might have.