VASP: Propietary plane-wave-based DFT implementation.
Quantum Espresso: Free plane-wave-based DFT implementation.
Phonopy: Set of helper scripts implementing a real-space supercell approach to phonon calculations. It relies on DFT software like VASP for obtaining the forces on atoms and the dielectric parameters; from those, it obtains 2nd-order force constants and many harmonic or quasiharmonic variables.
spglib: Free implementation of point-group symmetries, developed by Phonopy and used also by ShengBTE and thirdorder.py.
BoltzTraP2: Program for calculating electric conductivities and other electronic-band-structure-dependent quantities.
OpenBLAS: Highly optimized BLAS library under a free BSD license.
aflowlib.org: Public repository of ab-initio data for hundreds of thousands of compounds.
WebElements: Web site with a large number of basic properties of the elements.
The Materials Project: Another database of ab-initio data.