BreakPoint Software, Inc. Home of Hex Workshop, the Professional Hex Editor (and sector editor, base converter, and bit manipulator). [Commercial] http://www.bpsoft.com/
Hackman An advanced hex editor and disassembler. News, support and related products such as language packs, plugins and add-ins. http://www.technologismiki.com/hackman/
Shed Easy to use hex editor written for Unix/Linux using ncurses, with a friendly pico-style interface. http://shed.sourceforge.net/
The HT Editor A professional executable file editing tool which currently supports the MZ, PE and LE file formats including code analyser. For Windows and Unix. [Open Source] http://hte.sourceforge.net/
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