It would be a toss up between two of my old co-workers when I was a cart-pusher (shitty, horrible, soul-killing monotonous job). One was a stupid fucking idiot Juggalo who would always talk about ICP, being a 'real Juggalo', how he was a member of three gangs (Crips, Bloods and Juggalos) and how much drugs he'd used (coke and weed mostly). That was when he wasn't flaking off for hours at a time before showing up just long enough to go on his hour long lunch break or just not showing up at all.
The other one was a fucking jack-ass prick who repeatedly tried to get me fired because he didn't like me. He'd tell managers that I wasn't out on the lot working, told manger that I threatened to beat him up (twice) and was generally unpleasant to be around.
The world would probably be better off without either one of those fuck-heads running around.