GnuPlot - Gnuplot is a portable command-line driven interactive data and function plotting utility.
itch.io - An online game marketplace and community.
GeoGebra - GeoGebra is free and multi-platform dynamic mathematics software for learning and teaching.
GOG.com - DRM-free game store, selling both new and old titles. No clients required.
SciDaVis - SciDAVis is a free application for Scientific Data Analysis and Visualization.
Grapher - Put Grapher’s powerful graphing and data analysis features to the test and better understand your data. Learn about features and download a free trial.