Friday Forays in Fiction: What Makes Funny Funny?

I've been contemplating humor a lot this month as I work on my script, read, watch movies, peruse LOLcats. What makes funny funny? I haven't any words of wisdom or profound insights to share. I'm just sharing the fact that it is on my mind.

I'm too tired to form my thoughts into coherent sentences even if I did have something insightful to share. I've been awake since 2:30am and the pillow is whispering sweet nothings. Why was I awake at such an hour? Because I surrendered to a nap attack after dinner last evening and then slept a full 7 hours.

I do have one observation about humor that just occurred to me. It seems to have something to do with surprise. As I was writing the above paragraphs my memory flashed on half a dozen things from movies, conversation and LOLcats that have elicited laughter or giggles from me recently. And they all seem to have the element of surprise in common. It might be interesting to analyse those moments looking for more commonalities than surprise or attempt to establish that surprise is in fact the common denominator. But the pillows are starting to hum lullabies now.