This is a perl-ish way of renaming all files in a directory tree. This removes all non-word characters:

#!/usr/bin/perl

use File::Find;
use File::Copy;
use warnings;
use strict;

find ( sub  {
	 return unless -f ;
	 my $foo;
	 move($_, $foo) if  ($foo = $_) =~ s/\W//g;
       },
       '.' );

Here's a version that maintains extensions:

#!/usr/bin/perl

use File::Find;
use File::Copy;
use warnings;
use strict;

find ( sub  {
	 return unless -f ;
	 my $new;
	 move($_, $new ) if ($new = $_) =~ s/[^\w\.]|\.(?!\w+$)//g;
       },
       '.' );