To compile:
gcc pigz17.c -lpthread -lz -o pigz

Sample command line:
pigz -p 10 -v (filename)

The default 32 threads seems to be kind of high, drives load up quite
a bit, while 10 threads at least in a simple test on a 2GB file
kept load a lot lower but still kept the CPUs busy at 100% utilization
on a dual core system. YMMV.

original source:
http://zlib.net/pigz17.c.gz

if that doesn't exist there may be a new version, try pibz18.c.gz  19.c.gz ..etc


Usage: pigz [options] [files ...]
  will compress files in place, adding the suffix '.gz'.  If no files are
  specified, stdin will be compressed to stdout.  pigz does what gzip does,
  but spreads the work over multiple processors and cores when compressing.

Options:
  -0 to -9, --fast, --best   Compression levels, --fast is -1, --best is -9
  -b, --blocksize mmm  Set compression block size to mmmK (default 128K)
  -p, --processes n    Allow up to n compression threads (default 32)
  -i, --independent    Compress blocks independently for damage recovery
  -R, --rsyncable      Input-determined block locations for rsync
  -d, --decompress     Decompress the compressed input
  -t, --test           Test the integrity of the compressed input
  -l, --list           List the contents of the compressed input
  -f, --force          Force overwrite, compress .gz, links, and to terminal
  -r, --recursive      Process the contents of all subdirectories
  -s, --suffix .sss    Use suffix .sss instead of .gz (for compression)
  -z, --zlib           Compress to zlib (.zz) instead of gzip format
  -k, --keep           Do not delete original file after processing
  -c, --stdout         Write all processed output to stdout (won't delete)
  -N, --name           Store/restore file name and mod time in/from header
  -n, --no-name        Do not store or restore file name in/from header
  -T, --no-time        Do not store or restore mod time in/from header
  -q, --quiet          Print no messages, even on error
  -v, --verbose        Provide more verbose output