I am a firm believer in open-source code. Currently I am a contributor or developer to the following projects:
BurnMan is an open source mineral physics toolbox written in Python to determine seismic velocities for the lower mantle. BurnMan calculates the isotropic thermoelastic moduli by solving the equations-of-state for a mixture of minerals defined by the user. The user may select from a list of minerals applicable to the lower mantle included or easily define one of their own. See Cottaar et al., 2014 for more information. Funded through the Cooperative Institute for Dynamic Earth Research (CIDER) and hosted by the Computational Infrastructure for Geophysics. Available at burnman.org
The Arbitrary Composition Condensation Sequence Calculator (ArCCoS) is an equilibrium condensation sequence calculator. It calculates the distribution of 23 elements between ~400 gas phases and ~100 solid phases of interest to planetary and exoplanetary science. See https://arxiv.org/abs/1604.08309 more information. Available at my github.