Hackman
http://www.technologismiki.com/en/index-h.html
With Hackman Hex Editor you can edit any type of file in your hard disk, even your hard disk itself. Data are presented in 5 different ways ( modes):
ASCII, Hex, Binary, Octal, Decimal
Here´s a partial feature list:
Edit any binary file
Disk Editor
RAM Editor
Unlimited undo/redo with undo/redo lists
Clipboard control: cut, copy, paste, paste special, clear clipboard
Highly sophisticated find and replace
Unlimited watches and bookmarks
Numerous conversion modes, including Java, C++, VB, ASCII, text and more
Patch Maker
MS-DOS Executable Maker
Merger/Splitter
Checksums: CRC16/32, MD5, SHA1 and more
Cryptographic capabilities ( Skipjack, NSA, RCA algorithms)
Live update to constantly keep your copy up-to-date
Support for macros
Command bar
Numerous Plugins and External Tools
Highly customizable: reconfigure toolbar, shortcuts, menus, anything!
Supports column grouping
Available in many languages!
Unparallel extension capabilities: build your own plugins easily
Help books online
And more...