How about the old bleach invisible encoding like this:

my $string = "foobar";
my $enc = unpack 'b*', $string;
$enc =~ tr/01/ \011/;
print "This is \$enc '$enc'\n";
$enc =~ tr/ \011/01/;
print "Now this is \$enc '", (pack 'b*', $enc) , "'\n";
[download]

This is really hard to *see* let alone read - I'd call that a hidden field :-)

cheers

tachyon

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