I find it freaking annoying when people suddenly come up from behind me while I'm sitting at my desk at work to talk to me about trivial, non-work-related things. More often than not, they startle me. I startle very easily, and I really hate being startled. The sudden pang of fear physically feels bad.

Even if people are just trying to be social, I don't like the fact that they're barging in on me and whatever I'm doing on my laptop uninvited. They could choose to catch me in the breakroom, or drop by when my manager is not sitting a couple feet away from me. The entire building is quite quiet most of the time, so desk-side conversations can be heard by many. I dislike being forced to be rude.