8 free tools for science & data, 8 of them fully open source. Every one reviewed, with its licence and the paid apps it replaces.
Reference manager for collecting and citing sources

Notebook environment for code, data and visualisation

Geographic information system for maps and spatial data

IDE for R and data science projects

Numerical computing language largely MATLAB-compatible

Processing and editing of 3D triangular meshes

Electronics design suite for schematics and PCBs

Universal database client and SQL editor