IMMUNITY : Knowing You're Secure. Welcome to Immunity Debugger Download Immunity Debugger Here!
Immunity Debugger is a powerful new way to write exploits, analyze malware, and reverse engineer binary files. It builds on a solid user interface with function graphing, the industry's first heap analysis tool built specifically for heap creation, and a large and well supported Python API for easy extensibility.
A debugger with functionality designed specifically for the security industry Cuts exploit development time by 50% February 1, 2003. Zero: A Linux Debugger for C++ Apps.