ECMerge Pro

From Ellie Computing:

ECMerge compares and merges files and folders, side-by-side or 3-way. It provides syntax colouring for C/C , Java, HTML, ASP, PHP and many others. Save your work at intermediate situation and restart it later! Generate Unix patches between files. A shell extension is provided under Windows. A Linux version is available. Can be used as a replacement of many SCC own merge tool, for better display of changes and more efficient merges. The integrated XML pretty-printing filter allows great comparisons for XML files. In-line differences are detected (at word and/or character level). A security distance can be specified for 3-way file merges so as to attract user attention during risked merges.