In 15 seasons on the air (the 16th season began Wednesday), Trey Parker and Matt Stone have found a way to skewer just about every race, religion, interest group and orifice. They've taken on sacred cows and wallowed in cheap laughs. Surprisingly, a lot of times the groups involved weren't offended. In fact, the show has won Emmys, a Peabody and been nominated for a GLAAD award. But not everyone can take a joke, and sometimes the boys from Colorado manage to shock and offend just about everyone. Here are some of the most outrageous moments from their first 15 seasons.