I'm very often the last person in a room to understand a joke, and it seems like many of us can relate to that. However, as someone else mentioned I have noticed that I tend to make people laugh even when I'm totally serious. Through my early teens I was just confused by this, and kind of insulted, but eventually I found out that there are some observations or ways of describing things that occur to me that don't normally occur to most people, and when I make them many people find them amusing. So I kept doing that, except I tend to time it better and rehearse lines which worked before - in other words, it would in most cases be intentional rather than unintentional. And if something doesn't work (which quite often happens, no matter how funny you are), I just pretend I never said it and move quickly on to something else.
Most of the time the closest things I have to "jokes" with punchlines and the like are stories, most of them unflattering stories about myself. As far as the overall reception to my stories and interjections goes, though, I think I can more than hold my own with what I have.
There is a story I have about my sense of humour, which exposes stereotypes of AS but at the same time makes me feel better about how my stories and interjections are received. It's not a funny story, though.
The events of the story took place about one and a half years ago in college. One day, having finished another long quantum mechanics homework me and a certain classmate were the only people left in our little study room.
Suddenly he remarks to me, "that guy A, he definitely has Asperger Syndrome don't you think?" This came totally out of the blue; I never told him about AS before then.
"What?"
"You know, Asperger Syndrome. A mild form of autism."
"Yes, I know, but I never thought of A that way before."
"Well, he definitely does. It's so obvious. I'm on a private mission here, because I think a few people in our class may have it."
I wasn't too impressed, but I decided OK let's bring my diagnosis up. "Well, if you must know," I told him, "I have it."
"Really?" He did indeed seem surprised. "I could never have guessed."
He paused. "Well... Maybe," he said, "but you have a really active sense of humour."
Totally presumptuous of him of course, but I took it as a compliment. Well maybe he really thought it was "active" as in actively annoying, but I have my doubts.