I hate it when People come into my cube and do not even ask "Is this a good time?" despite the fact that I have headphones on. I hate the fact that People take the fact that I turn around and say "Yes?" when they step into my cube as "Please, tell me your silly problems that you have not submitted a ticket for so that I may drop all my other Really Important Stuff to help you figure out why a machine is not working."
I especially love it when People expect me to be psychic and find out the information I need from picking it out of the Ether. Because that is what my job description is "Psychic Network Architect". No, really, it is. I have business cards.
I also hate People who, when I spend $1500 on appliances from their store, screw up my order. I hate it when People charge me for an installation of a dishwasher, yet do not bother to actually schedule said installation for me, so when the delivery People call they say "what installation?".
But I'm not bitter.