ampl : A comprehensive, powerful and flexible algebraic modeling language for the linear, nonlinear and integer programming problems often encountered in optimization.
gams - General Algebraic Modeling System : GAMS is a modeling system for mathematical optimization problems, both linear, non-linear and mixed-integer.
Gnumeric - The Gnome Office Spreadsheet : The Gnumeric spreadsheet is part of the GNOME desktop environment: a project to create a free, user friendly desktop environment.
Usage: tar [ - ] A --catenate --concatenate | c --create | d --diff --compare | --delete | r --append | t --list | u --update | x --extract --get [ options ] pathname [ pathname ... ]
The GIMP : The GNU Image Manipulation Program or just GIMP is a Free Software bitmap graphics editor, a program for creating and processing raster graphics.
Pine - a Program for Internet News & Email : Pine - a Program for Internet News & Email - is a tool for reading, sending, and managing electronic messages.
Twm (Tab Window Manager) : Twm (Tab Window Manager, or sometimes Tom's Window Manager, after the principal author Tom LaStrange) provides titlebars, shaped windows, several forms of icon management, user-defined macro functions, click-to-type and pointer-driven keyboard focus, and user-specified key and pointer button bindings.
GDB: The GNU Project Debugger : GDB, the GNU Project debugger, allows you to see what is going on `inside' another program while it executes -- or what another program was doing at the moment it crashed.
DDD - Data Display Debugger : GNU DDD is a graphical front-end for command-line debuggers such as GDB, DBX, WDB, Ladebug, JDB, XDB, the Perl debugger, the bash debugger, or the Python debugger
eclipse : Eclipse is an open source community whose projects are focused on providing an extensible development platform and application frameworks for building software.