LyX is a document processor that encourages an approach to writing based on the structure of your documents, not their appearance. It is intended for people people who write and want their writing to look great without tinkering with formatting details, font attributes, or page boundaries. On screen, it looks like any word processor, but it uses the TeX engine for printed output and producing richly cross-referenced PDFs. It is stable and fully featured.
GNU TeXmacs is a free wysiwyw (what you see is what you want) editing platform with special features for scientists. The software aims to provide a unified and user friendly framework for editing structured documents with different types of content: text, mathematics, graphics, interactive content. TeXmacs can also be used as an interface to many external systems for computer algebra, numerical analysis, and statistics. New presentation styles can be written by the user and new features can be added to the editor using Scheme.
Papyrus is a XML-based reporting langauge for PostgreSQL and MySQL. It allows you to generate well-formatted reports in LaTeX, PDF, PostScript, HTML, ANSI, and XML. The XML is expressed in a formatting-oriented style to allow you to develop a wide range of reports. SQL is then embedded into the report to give you the desired data. Papyrus is commandline-driven, and data arguments can be passed into the report. Equations and expressions can also be carried out on data.
gnome-courier is a collection of programs for courier services. It includes programs for managing clients, managing coworkers, managing jobs (receiving, distributing, and editing), printing bills and overdue notices, and managing the payroll. Various statistical modules are available, and since the project is based on a modular concept, it can easily be extended.