Ever feel like you're ready to go home as soon as you crank up your car...in your driveway...on the way to work? That's the general atmosphere at my job. But I'm leaving in the very near future, so it's cool.
Co-workers: People that sit around and either stir up drama or keep it going by forever gossiping about everyone. You're ruining my concentration on the job, and the atmosphere is negatively charged. Thanks! You add a lot to the workplace.
Also, those people that can't do their jobs to save their lives, but they want to slow down your progress by constantly asking for your help. Can you retain any information that you're given? Throw me a friggin bone here.

Extra irk points for having the gall to question my answer when you were looking for an answer. If you have all the answers, then why are you in my periphery?
Supervisors/Management: Bosses that don't have the cajones to make decisions, enforce rules, or issue write-ups/have a conference/etc. You're paid a salary for a reason, and it is not limited to your ablility to generate reports or delegate. If you can't speak to your employees about what your expectations for their job performance or you can't reprimand the regular offenders, you do not have the respect of your team. (True story happening to me right now. That's why a sista is about to be out!)