OmniHelp is a cross-platform, browser-independent, tri-pane help viewer built in pure JavaScript and CSS with HTML 4. Some functions (such as help embedding) may in the future be in Java, C, or C++; CSH is fully supported. All code is under the LGPL.
WebSHi (Web Syntax Highlighter) is just another code syntax highlighting engine. Though it's written in JavaScript, WebSHi is very fast and scalable, can process 30,000+ lines of code in seconds even on slower browsers like IE6.
MOStlyCE is a "What You See Is What You Get" (WYSIWYG) editor for the open source Mia Content Management System (MiaCMS). MOStlyCE aims to bring simply, yet power, HTML editing capabilities into the hands on the average user.