Kile is a user-friendly TeX/LaTeX editor for the KDE desktop environment. It lets you compile, convert, and view your document with one click and features auto-completion of (La)TeX commands, templates and wizards for starting a new document, easy insertion of many standard tags and symbols and the option to add user defined tags, inverse and forward search, collection of documents that belong together into a project, easy insertion of citations and references, a flexible build system, QuickPreview of selected parts of a document, easy access to various help sources, and advanced editing commands.
Eric is a full featured Python and Ruby editor and IDE, written in Python. It is based on the cross platform Qt GUI toolkit, integrating the highly flexible Scintilla editor control. It is designed to be usable as an everyday quick and dirty editor as well as being usable as a professional project management tool, integrating many advanced features that Python offers the professional coder. Eric includes a plug-in system, which allows easy extension of the IDE functionality with plug-ins downloadable from the net. Current stable versions are Eric4 based on Qt4 and Python 2 and Eric5 based on Python 3 and Qt4.
Co-Ment is a Web service for annotating, discussing, and writing texts online. The editing environment is wiki-like, supporting many syntaxes (Markdown, RST, and HTML), and allows for finely controlled layouts including tables and images. Users can comment on extracts of the text, and advanced comment navigation features allow new annotations to be discovered or the history of a debate to be browsed. It is also possible to set up an email alert for text edits or new comments. Import/export is supported for many formats including TXT, DOC, ODT, and HTML.