In one way or other, researchers in the multiphase area, especially those seeking to identify and capture distinct interface between liquid / liquid or liquid -gas, have come across the SOLA VOF code.
A publication on the computational method for free surface hydrodynamics (SOLA VOF method) can be found here.
Discussions in the cfd-online forum pertaining to the availability of the free VOF code - SOLA VOF is linked here
In particular, one of the guests posts the link to the download of the report containing the SOLA VOF code -in an as-is basis. The LANL server hosts the file (link below)
The report above, contains the complete description of the solution derivation of the transient fluid flow with free boundaries (2D computer program)