itch.io - An online game marketplace and community.
IGOR Pro - Technical graphing and data analysis for Macintosh and Windows.
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.
GnuPlot - Gnuplot is a portable command-line driven interactive data and function plotting utility.
LabPlot - LabPlot is a KDE-application for interactive graphing and analysis of scientific data.