here's my first try on obfuscation
maybe i got to much time at work ;)

                        $_="What is this?"
                     ;my@t=unpack("C*",$_);my@
                   o;$o[0]=$t[0]-$t[12]+$t[9]-$t
                [6]+$t[2]+$t[9]-$t[10];$o[1]=$t[3]
             +$t[8]-$t[1]-$t[12]+$t[0]-$t[6]+$t[8]-$
            t[10];$o[2]=$t[12]+$t[7]+$t[8]-$t[9]-$t[10]
           +$t[3];$o[3]=$t[9]-$t[12]+$t[9]-$t[7]-$t[8]+
           $t[9];$o[4]=$t[8]-$t[0]+$t[6]-$t[10];$o[5]=$
            t[6];$o[6]=$t[7];$o[7]=$t[10]+$t[9]-$t[12]
            -$t[7]-$t[8]+$t[9];$o[8]=$t[5];$o[9]=$t[3
             ]+$t[8]-$t[12]-$t[0]+$t[4];$o[10]=$t[6];$
            o[11]=$t[3];$o[12]=$t[7];$o[13]=$t[0]-$t[
              12]-$t[6]+$t[2]+$t[10];$o[14]=$t[9]-$t
               [12]-$t[7]-$t[8]+$ t[9]+$t[9]+$t[9]
                    -$t[    12]-$t[7]-
                            $t[8]+$t[9           ];$
                            o[15]=$t[9         ]+$t[10]
                            -$t[12]-$t      [7]-$t[8]+$t
                            [9];$o[16]=$t[3]+$t[8]-$ t[11]
                            ;$o[17]=$t[6];$o[18]=
                            $t[9]-$t[12]-$t[7]-$t
                            [8]+$t[9]+$t[9]+$t[9
                            ]+$t[10]-$    t[12]-
                            $t[7]-$t[8    ];  $o
                            [19]=$t[2]    ;$  o[
20]=$t[3];$o[21]=$t[9]+$t[10]-$t[9];$o[22]=$t[0]-$t[12]-$t[6]+$t
[2]+$t[10];$o[23]=$t[0]-$t[12]+$t[9]-$t[6]+$t[2];print pack ("C*",@o);

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In reply to first obfuscation by m0ve

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