GnuPlot - Gnuplot is a portable command-line driven interactive data and function plotting utility.
Goophy for G Suite - Easily add animated gifs to your docs with just a few clicks. Just search for gifs and click to add. (Powered by the Tenor Gif API)
Dr. Geo - Dr. Geo, a software to design & manipulate interactive geometric sketches.
MindMeister for G Suite - MindMeister lets you create, share and collaboratively work on mind maps.
Giac/Xcas - Free computer algebra system
BeeCanvas for G Suite - BeeCanvas is visual collaboration tool. All of your ideas in one place. It's the easiest way to express thoughts and communicate clearly with your entire team.