wxHexEditor is an open source cross-platform disk/sector/file hex editor written in C++ with a wxWidgets-based user interface.
The project seems no longer developed since 2020. Last version, 0.24, released in December 2017, can be still downloaded from SourceForge and GitHub
WinHex is a hexadecimal editor capable of opening disks, sectors, files (native support for FAT, NTFS, Ext2/3, ReiserFS, Reiser4, UFS, CDFS, UDF) and physical memory (RAM). It can read, write and extract data for a further forensic analysis.
Bless is a high quality, full featured hex editor. It is written in mono/Gtk# and its primary platform is GNU/Linux. However it should be able to run without problems on every platform that mono and Gtk# run on.
Hex Editor Neo is a binary files editing software utility for Windows. It's rich and handy set of features will help all software and hardware developers working with ASCII, hex, decimal, float, double and binary data.
FileAlyzer is a tool to analyze files, allows a basic analysis of files (showing file properties and file contents in hex dump form) and is able to interpret common file contents like resources structures (like text, graphics, HTML, media and PE).
The Hex Workshop Hex Editor by BreakPoint Software is a complete set of hexadecimal development tools for Microsoft Windows 2000 and later. Hex Workshop combines advanced binary editing and data interpretation with the ease and flexibility of a modern word processor.
Frhed(Free hex editor) is an binary file editor for Windows. It is small but has many advanced features like ability to load big files partially. String replacement, multi-language, and other features.