|Sometimes I laugh at the wrong stuff. Not like murder or cancer or anything, but just things that aren't supposed to be funny but sound funny in my head.
For example, I was listening to a co-worker tell a story a few weeks ago. In the story, he was casually mowing his lawn when he got hit on the head by a golf ball, which sent him to the ground. He got up swinging and yelling because he thought somebody had attacked him from behind. It turned out it was his stupid neighbor who didn't realize golf balls shouldn't be hit in the direction of people.
Right as he said the part about the ball hitting his head, I laughed. On the one hand, I can't even fathom how much it would hurt to get hit by a golf ball, especially on the head. I would imagine it would rank up there with a concussion, giving birth, or breaking a bone. I have no doubt that this guy felt some serious pain, that it was a serious situation, and that serious situations don't include laughing.
On the other hand, I got a funny picture in my head. The picture was actually more of a movie, and it involved two separate funny things: The sound the ball could've potentially made as it hit this guy's head, and the distance it likely traveled post-ricochet. The sound I imagined was like knocking on a hollow tree: *clock*. Weeks later, I'm still laughing at this sound in my head. It helps that I've heard a similar sound, though thankfully not from a golf ball impacting a person's skull. The ricochet is a whole other funny thing. If you've ever witnessed a speeding golf ball hitting a solid object, you'd know that those things can fly. I've seen golf balls fly off trees, pavement, and rocks. It's truly breathtaking. So the picture of a golf ball hitting a solid object called "this dude's cranium" is just too good to not laugh at.
Thankfully I'm pretty good at making people think I'm a nice, civilized person, so I recovered my laugh into a "ha ha hh-wow that's unbelievable." The guy went on to say he didn't suffer any permanent damage, so no harm, no foul.
Update: This Dilbert comic agrees. #psychology