"Positively Positive Crew"- Acronym made famous by such hardcore/metal bands as In the Face of War and Kingston Falls which stands for "Positively Positive Crew". Staying clean and positive all the time and avoiding violence.
Excerpt from Kingston Falls Myspace: For everyone who wants to be positive in every aspect of life, join our crew, ppc. It stands for positivly positive crew. Practice being friendly and positive to everyone around you and when you start to get mad, simply say "it's alright, ppc". That's when you hit your fist together on the knuckles and everything is good. In order to be in this crew, simply put ppc (with the brackets) and we'll love you forever. Have fun with it guys!!