DiffDog Standard Edition 

Altova DiffDog 2005 Standard Edition is the dedicated differencing utility for developers and power users. This easy, powerful synchronization tool quickly compares files and folders then highlights differences and merges content via an elegant GUI.
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DiffDog Professional Edition 

Altova DiffDog 2005 Professional Edition is the developer's dedicated differencing utility. This unique XML-aware synchronization tool quickly compares files and directories then highlights differences and merges content via an easy visual interface.
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AJC Diff 

This program compares two files. Files can be shown combined or side by side. Full diff, context diff or differences only. Color coding, line nos, search and print options.
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