Sorry, I can't name the sub after myself since ;-) doesn't compile :)

sub cLive {
    my $rev = reverse $_[0];

    my $len='';
    my $d;
    for (0..length($_[0])-1) {
        my $c= join'',map { substr($rev,$_,1) eq substr($_[0],$_,1) ? 
+1 : 0 } 0..length($_[0])-1;
        my $match = (sort {length($a)<=>length($b)} $c =~ /(1+)/g)[-1]
+;
        $match>$len and $len=$match and $d=$c;
        $rev = substr($rev,1).substr($rev,0,1);
    }
    $d=~s/(.*)($len).*/substr($_[0],length($1),length($len))/e;
    return $d;
}
[download]

cLive ;-)

ps - if more than one longest palindrome, first is returned.