What is not referred to as a gang, but a "brotherhood" that makes up their own words and does drugs. It was started by some white and mexican stoners in the Waterloo/Cedar Falls area of Iowa. It stands for "George Keetness Garbage."
"Whoa, dude, look at that group of G.K.G.'s beating up that little black kid!"
"Yeah, I know man, but it's okay though because I just scored some good shit from those bastards!"