"little Johnny can't visit any website where the domain component of the URL ends in the string “.xxx”, in which case all little Johnny has to do is go to a web

"little Johnny can't visit any website where the domain component of the URL ends in the string “.xxx”, in which case all little Johnny has to do is go to a web-based nslookup tool, type in the domain he wants to look at, and then replace the domain with that IP address." Sounds like a good opportunity for nslookup tools to justify requiring a credit-card payment for certain types of lookup.