Ophcrack is a free Windows password cracker based on rainbow tables. It is a very efficient implementation of rainbow tables done by the inventors of the method. It comes with a Graphical User Interface and runs on multiple platforms.
PWNtcha stands for "Pretend We’re Not a Turing Computer but a Human Antagonist", as well as PWN capTCHAs. This project’s goal is to demonstrate the inefficiency of many captcha implementations.
K. Khor, J. Buffiére, W. Ludwig, and I. Sinclair. Scripta Materialia, 55 (1):
47 - 50(2006)Viewpoint set no. 41 "3D Characterization and Analysis of Materials" Organized by G. Spanos.