Hex Workshop - Hex Workshop: Hex Editor, Sector Editor, Base Converter and Hex Calculator for Windows
BinHex CryPactor - Manipulate binary and hexadecimal strings!
HextEdit - HextEdit is a proficient hex editor and disassembler for Mac.
FlexHex - FlexHEX is a full-featured hex editor designed to edit binary files, OLE compound files, logical devices, and physical drives. With FlexHEX you can inspect, modify, insert, search, or replace binary, ASCII, or UNICODE data.
DHEX - Themeable hex editor with diff mode for tracking file changes.
iHex - iHex is the premier hex editor and data analysis tool for Mac OS X.