(noun) stands for Pure Crystal Based Shit. The way to express one's excitement over something. It means awesome, epic, amazing, cool, radical, intense, life-changing.
"Yo man that's total PCBS stuff right there."
-"Do you use Old Spice deodorant?"
-"Ya man, PCBS all the way!"
-"What kind of weed do you have?"
-"I've got some PCBS that will blow your mind!"
"I just won an award for best music video category... PCBS!"