Child pornography
Child Pornography is basically kids who appear in a playboy magazine. It's one of the most widespread, controversial and devastating criminal activities in the modern world - though it has existed since prehistory the advent of the internet has made the crime an international concern and most governments crack down ruthlessly on those found in possession of such materials.
Stopping Child Pornography and capturing those involved is a top-priority of most child-welfare groups and police officers dealing with pedophile rings and child-abusers.