Happy birthday, Jackass! The venerable gonzo-stunt MTV series that turned ringleader Johnny Knoxville and his extreme-stunt-loving skate-rat crew into stars turns 15 today — and in honor of this momentous poo-stained anniversary, we've asked the gents to spill the beans on their most outrageous moments. Ever wonder who suffered the worst in the "anaconda ball pit," or how exactly one rigs a "poo-cano," or what was going through Steve-O's mind as he flew through the air in a shit-filled Porta-Potty? (Answer: It wasn't pretty.) Fire up the Minutemen's "Corona" and read on. Don't say we didn't warn you.