When the cold you've been dealing with for the past several days travels from your sinuses down into your chest. So, you go from having a super runny nose to a horrible cough not to mention a soar throat to a scratchy/phlegmy one. T_T
When I pick up an obvious spelling/grammatical error in a PM after I've sent it, and the other person has read it. They may be too polite to say anything, but it irks me, XD. I just want to grab the PM back and re-send it.
When the newbie at work keeps making small mistakes over and over again, but they're so minor you don't feel the need to tell him, but at the same time, he keeps making them. It's like... GAH! QUIT IT ALREADY! OR DO SOMETHING BIG ENOUGH FOR ME TO TELL YOU OFF!