"I disagree with your correspondents who argue that computer games are not the sole cause of today's violence problems (Metro, Wed). Just the other day, after playing Mario Kart, I bought some bananas and while driving home I started to throw the skins at passing cars in an attempt to make them spin out of control. I can't help but think that had Mario Kart been awarded an 18 certificate, I may have thought twice before behaving in such an immature and dangerous manner."