My updates to David Kendall's original, and now part of tools-osx (https://github.com/morgant/tools-osx).

clipcat

#!/usr/bin/perl -w

# 
# clipcat - Concatenate and print Text Clippings.
# 
# v0.1   2010-11-18 - David Kendal <https://gist.github.com/705623>
#                     Initial version. Used with permission.
# v0.2   2010-12-08 - Morgan Aldridge <morgant@makkintosshu.com>
#                     Now concatenates multiple text clippings. Usage instructions.
# 

use strict;
use utf8;
use MacPerl;
use File::Basename;

my $script = basename($0);

if ($ARGV[0]) {
  while ($ARGV[0]) {
    my $file = $ARGV[0];
    my $fileinfo = MacPerl::GetFileInfo($file);
    
    $file = escape($file);
    
    if (!-e $file) {
      print STDERR "$script: no such file $file.\n"; exit 1;
    } elsif ($fileinfo ne 'clpt') {
      print STDERR "$script: file $file is not a clipping.\n"; exit 1;
   }
    
    my @resdata = `DeRez -only 'utf8' '$file'`;
    shift(@resdata);
    pop(@resdata); pop(@resdata);
    
    foreach (@resdata) {
      my $line = $_;
      chomp $line;
      $line =~ s{^\t\$"|" +/\*.+\*/$}{}g;
      my @blobs = split / /, $line;
      foreach (@blobs) {
        my $blob = $_;
            
        my $hex1 = substr $blob, 0, 2;
        my $hex2 = substr $blob, 2, 3;
        
        print chr(hex($hex1)).chr(hex($hex2));
      }
    }
  
    shift(@ARGV);
  }
  exit 0;
} else {
  print STDERR "$script: No files were specified.\n\n";
  usage();
  exit 1;
}

sub usage {
  print "Usage: clipcat [options] file ...\n";
  print "    -h            print these usage instructions\n";
}

sub escape { # http://cl.ly/3JGN -- should work to escape the filename
  my $text = shift;               # for handing to DeRez
  $text =~ s/\\/\\\\/g;
  $text =~ s/'/\\'/g;
  return $text;
}