I was pretty sure I was getting somewhere with this approach, but I ended up at 54 characters, just like chipmunk. 
    sub crypto{
    ($_,$a,%h,$h)=@_;s/./chr($h{$&}||=vec$a,$h++,8)/gse;$_
    }

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In reply to Re: (Golf) Cryptographer's Tool #1 by tadman
in thread (Golf) Cryptographer's Tool #1 by Masem

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