Info-ZIP's UnZip 5.12:  generic C sources
  Complete C source code for Info-ZIP's
  PKUNZIP-compatible unarchiver, for all
  supported compilers and platforms (Unix,
  OS/2, MS-DOS, NT, VMS, Amiga, Atari, Mac,
  etc.), plus lots of cool documentation.
This is FREE (but copyrighted) software.
See COPYING for details on distribution
and reuse.