Project page: http://os2progg.by.ru/pde/
"The PDE Shell is the free alternative user shell for OS/2 and eComStation. The new version PDE contains the great number of changes and useful possibilities, which will do your work more pleasant. Main changes in PDE 0.20 are done on availability and simplicity of the use. Huge work on simplification was done options and the PDE tuning."
Source: