TEA is a powerful and easy-to-use Qt4-based editor with many useful features for HTML, Docbook, and LaTeX editing. It features a small footprint, a tabbed layout engine, support for multiple encodings, code snippets, templates, customizable hotkeys, an "open at cursor" function for HTML files and images, miscellaneous HTML tools, preview in external browser, string manipulation functions, Morse-code tools, bookmarks, syntax highlighting, and more.
Blyte is a program for writing movie screenplays. Compared to a normal word processor, it is easier, faster, and more efficient for writing scripts, since it knows how scripts are put together. It can thus predict what you want to do next, automatically find errors, format the script correctly, and much more.
Evergreen is a cross-platform development environment that tries to be lightweight and language-agnostic yet functional. It started as a project to reimplement Rob Pike's Acme editor for Plan 9 in Java, but has since evolved in directions that help it deal with large codebases and multiple projects/branches at once. Remaining similarities include the tiled windows and the Unix-like reliance on external programs rather than reinventing every wheel. The major philosophical differences include strong support for keyboard-based editing, language-specific functionality, and native platform UI conventions. There are also two new guiding principles: accepting regular expressions and output diffs.