Phoenix is a modern open-source Code Editor for the web
Vivid3D is a C++ IDE/3D engine, with python scripting.
Free, open-source browser IDE for HTML, CSS & JavaScript.
Browser-based compiler and IDE
Web IDE in single HTML file
Extensible HTML5 app for real-time collaborative projects
A full-featured web-developing tool including website and FTP managers
Game creation engine with built-in BASIC interpreter.