This is the first time I used tie for anything other than tieing an array to a file. Not terribly obscure, but I thought it was a nifty trick.

use strict;use warnings;tie my$t,'A';$t=".rekcah lreP rehtona tsuJ";
print while$_=$t;package A;sub TIESCALAR{bless\my$s,shift}sub STORE{
${$_[0]}=$_[1]}sub FETCH{chop${$_[0]}}
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As an added bonus, this one runs fine under strictures and warnings.