WWPACK
From Just Solve the File Format Problem
WWPACK is an executable compression and file compression utility for DOS, developed by Piotr Warezak and Rafal Wierzbicki. It does executable compression of EXE files. It can also compress arbitrary data files.
Some of the files compressed by WWPACK can be decompressed by WWPACK, using the "U" or "UD" option.
Identification
EXE files compressed by WWPACK probably have ASCII "WWP"
at offset 28.
Data files compressed by WWPACK begin with "WWP"
.