From the article:
The most controversial games tend to come from within the indie developer community, where you don't have to worry about funding or even about turning a profit. Here you can find all manner of subject matter, from a virtual torture simulator, to a game in which players step into the role of a terrorist in an attempt to assassinate the president. But the most infamous indie game has to be Super Columbine Massacre RPG!. Created by film student Danny Ledonne and released in 2005, the game chronicles the last day in the lives of the shooters responsible for the Columbine High School Massacre in 1999. The game was not the first project to look at the Columbine tragedy. Michael Moore's 2002 documentary "Bowling For Columbine" won numerous awards, while the novel "Hey Nostradamus!" by Douglas Coupland used the event as inspiration for a fictional school shooting in the suburbs of Vancouver, which served as the catalyst for an exploration of the effects of tragedy spanning decades.
As you can see, there's some pretty scary stuff out there. And it's just the beginning.