Codes pw2bgw.x convert data files from pw.x to a format suitable for usage by the Berkeley GW code. See file Doc/INPUT_pw2bgw.* for input data documentation. Code bgw2pw.x, performing the inverse conversion, no longer works: a copy that worked for the old file format is kept for reference in bgw2pw.f90.orig.
Code pw2gw.x converts data files from pw.x to a format suitable for usage by another GW code, computes optical properties in single-particle approach (Fermi Golden Rule). See file Doc/INPUT_pw2gw.html for input data documentation, directory pw2gw_example/ for an example of usage.
Code open_grid.x writes Kohn-Sham orbitals for the complete k-point grid (not symmetry-independent points only) in real space. Useful for further processing. It can be used to generate the Kohn-Sham state data required in pw2wannier.x and Wannier90 from the initial SCF calculation, bypassing the non-SCF calculation step.
Code pw2critic.x is an interface to the CRITIC2 code by Alberto Otero-de-la-Roza. This program creates a pwc file containing the Kohn-Sham orbitals from an SCF calculation (or from the output of open_grid.x). These orbitals are used for post-processing in CRITIC2.
Code pw_export.f90 no longer works and is no longer present.