What's is one person that you hate or can't stand and why?

I hate social climbers. They can jump off a cliff. I also hate most call center agents. Seriously, they're giving their profession a bad name. They suddenly feel like international CEOs just because their job requires them to speak in English (while at the same time eating in the same cheap places as most of us do). Moreover, most of them actually suck in English. They use this obviously forced and horrible sounding accent that they think makes them sound like natural Americans--even when they don't have to.