Who hasn't gotten in an elevator and looked up at the ceiling or straight ahead, but can you imagine some intentionally messing with you?

I don't know what my deal is, but even when I am in an elevator with someone I know, I barely speak a word. And that is saying something for me, who never shuts up. :) What is it about elevators that make people so uncomfortable? Must be the lack of personal space, and worry that you will get stuck.