GLE (Graphics Layout Engine) is a graphics scripting language designed for creating publication quality figures (e.g., a chart, plot, graph, or diagram). GLE supports various chart types (including function plot, histogram, bar chart, scatter plot, contour plot, color map, and surface plot) through a simple but flexible set of graphing commands. More complex output can be created by relying on GLE's scripting language, which is full featured with subroutines, variables, and logic control. GLE relies on LaTeX for text output and supports mathematical formulae in graphs and figures.
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.
METAGRAF is a graphical editor for creating figures in MetaPost. It is currently able to draw any kind of figure in b/w or color. METAGRAF outputs a MetaPost file which can then be run through MetaPost by itself or using TeX. The program is written in Java and is thus platform-independent.
Sixpack is a graphical and command-line bibliography database manager written in Perl/Tk. It interacts with the supplied package 'bp', which can import and export from a number of formats including bibtex, endnote, medline, procite, and many others. It can download references directly off the Web, and open articles using external viewers. It can also interface with Emacs/XEmacs and Lyx.
TkDVI is a DVI previewer built with the Tcl/Tk toolkit. It can use multiple windows to display multiple pages at the same time (which can come from multiple DVI files sharing a common font repository). Each window can show either a single page, two facing pages (as in a book) or sixteen reduced pages in the space of one, to check page breaks and positioning of floating items. TkDVI supports many features from xdvi, such as a magnification glass, but also adds interesting stuff like a gv-like page selector and a `rubber line' for measuring distances. TkDVI is based on a reusable Tk `image type' for DVI files which can easily be incorporated in other programs, and it is straightforward to customize and extend TkDVI itself.