LibreOffice - Writer - Open-source cross-platform word processor.
Novelize - Novelize is an online novel writing app designed to keep authors on track.
AbiWord - AbiWord is a free software word processor.
Manuskript - Open-source tool for writers.
Atlantis Word Processor - Atlantis Word Processor enables users to create documents and reports and to publish e-books.
BlankPage - Stay motivated to write, and finish your story