Frhed (free hex editor) is a small, fast and powerful binary file editor.
Features include search and replace for any combination of binary and text data,
file comparison, bit manipulation, customizable display colors and font size,
ANSI or OEM character set, cut and paste, bookmarking and more. With Frhed you
can also apply binary templates for structured information, load files partially
(for working on huge programs), and export as hexdump to file or clipboard.
Frhed currently does not support Undo.
and editing with unlimited undo, multiple windows, auto-save,
session-recovering, spell-checking, calendar, games, ...
some say, it is a powerfull operating system (lisp) with a cryptic editor...