Curses Hexedit . Seems to be a good and useful editor. Has some extra nice functionality, see the infos taken from it's homepage below. Curses Hexedit is a full screen hex editor using the curses, ncurses , or pdcurses library. Allows Inserting and Deleting bytes from the file.
Highlights changes in the file in bold.
Fast boyer-moore string and byte searches. Undo - keeps track of all changes, reverting back to original always possible. There should be a site where different programms that do the same task are listed and compared. Ideal would be if every page could be maintained by a different person that is interested in the stuff, so it can keep up with the news.