Launch an external diff tool like WinMerge in Eclipse
A fast, portable, simple, and free C/C++ IDE
EditBox is the Eclipse plugin for source code background highlighting.
Open-source, cross platform Qt based IDE for reverse-engineering
Programming in MS Paint
Pascal XE is an easy to use IDE for Pascal programming.
A visual-based IDE for C language uses block drag and drop technology
Literate programming for eclipse
Light-weight Scintilla-based text editor with syntax highlighting
a DSL for type systems, reduction rules, interpreters for Xtext langs
Jxt4RunPlusJ is a source code editor and creator.
Graph algorithms interpreter, IDE, debugger, 3D visualizations.