Viking is a free/open source program to manage GPS data
Google maps for block game
OpenGrADS provides extensions and interfaces for GrADS.
TI graphing calculators <-> computer communication software
A 3D simulator game where you can drive, fly, and sail
ScholArxiv is an open-source aesthetic and minimal app
native Grace for Windows, Linux and Mac OS X based on Qt
Version 2 of the myFocuser Project
Open source finite element software for multiphysical problems
Open source Health IT for the planet
CloudCompare main repository
OctoPrint is the snappy web interface for your 3D printer
Toolkit for working with and mapping geospatial data
DXF2GCODE: converting 2D dxf drawings to CNC machine compatible G-Code
VHDL 2008/93/87 simulator