10. Goatse
No matter how much you might admire the flagrant anti-social naughtiness of the meme dedicated to it, there is nothing "sexy" at all about the Goatse internet phenomenon, or indeed the worrying, and painful looking behaviour it stems from. FOR THE LOVE OF GOD DON'T GOOGLE IT. Following on from their other Meme references - such as the Courage Wolf nod, and the brief little allusions to internet phenomena like Turtle Boy, the game also includes a thankfully tasteful reference to the Goatse meme. As you drive around Rockstar's giant world, look out for the number plates of passing taxi cabs - as a "celebration" of the meme, some of them carry the registration number "80AAT533". One for the eagle-eyed, certainly, and perhaps not one you should be particularly pleased about discovering, given what that say about your internet-based recreational activities. And that's not the only anal reference...