I'm still figuring out what I can joke about in my current office. (I'll stop being coy about where I'm temping: it's the main TriMet office, near my home.) A lot of my thoughts make me inwardly laugh and outwardly smile, after which I'll think Okay, better not say that.
I am managing to make jokes with the permanent workers. They're a thoughtful, friendly bunch. And they're NOT MEAN, unlike several of the people in my last office. So I don't feel the need to retreat into my headphones. I want to engage them! I want to amuse them. So that's a goal.
Good thing my thoughts don't have to be work-safe.
(Further Edit: And out-of-context thoughts, too; I'd better not say them, like this afternoon when I found myself mentally quoting Red Dawn. "Avenge me! Avennnnnnge meeeeee!")