GeoGebra CAS Calculator - Free online algebra calculator from GeoGebra: solve equations, expand and factor expressions, find derivatives and integrals
SciDaVis - SciDAVis is a free application for Scientific Data Analysis and Visualization.
Dr. Geo - Dr. Geo, a software to design & manipulate interactive geometric sketches.
OriginLab - OriginLab is a data analysis tool that provide the engineers and scientist with the technical charts and system for 2D and 3D plotting and all kind of fitting including curve and peak fitting.
Giac/Xcas - Free computer algebra system
LabPlot - LabPlot is a KDE-application for interactive graphing and analysis of scientific data.