Well I was just flipping thru my Mastering Perl/Tk and came across this code, which almost does what you want, just with Tk::Thumbnail. I just globbed for all jpgs , but it uses a small amount of memory, and you should be able to figure out how to work your file-find routine into it.

It also has a command to identify the thumbnail which you could use to open the photo in another toplevel window when you click on a thumb.

#!/usr/bin/perl -w
use Tk;
use Tk::Thumbnail;
use strict;

#adapted from Mastering Perl/Tk 

my $mw = MainWindow->new;

my $tn = $mw->Thumbnail(
    -images     => [<*.jpg>],
    -command    => sub {
        my $i = $_[0]->cget(-image);
        print "args=@_, image=$i\n";
    },
    @ARGV);
$tn->pack;

MainLoop;
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