I understand the (arguable) necessity and the prolific scams, but it seemed cruel to broke teenagers.
This was also one of the only ways for a broke middle schooler without a credit card to get a cool "real" domain.
Combine it with dyndns, self-host some ancient-but-free bulletin-board software (Woltlab Burning Board may ring a bell for the European / German audience) after learning about this "Apache2" and "mod_php" thing and your small slice of internet with 10 users max is done. Good times. :D
Have this instead “How a Tiny Pacific Island Became the Global Hub of Cybercrime”
Or used JavaScript tricks to hide the ads, or redirect the outer page to an ad-free URL. I know you could do the former on cjb.net, but perhaps .tk required the latter.