Though there are many, one of the most memorable lines from last summer's The Dark Knight is "this is what happens when an unstoppable force meets an immovable object."

It's such a great line and was perfectly used in the context of the movie. But recently, I've heard it pop up in a number of other places from the past too.

First, I heard it in a Wrestlemania clip, when the announcer referred to the Hulk Hogan vs. Andre The Giant match as the same thing. "This is the unstoppable force versus the immovable object!" or something to that length.

And then, I was listening to Pulp's classic This Is Hardcore album yesterday and the song "Seductive Barry" included this (hilarious) verse:

I've wanted you for years. I only needed the balls to admit it. When the unbelievable object meets the unstoppable force, there's nothing you can do about it.

I guess the unstoppable force here is, oh you know, lust. And the unbelievable object would be some vivacious lady. But it works to the same effect.

And a quick search around the internets would indicate that this line has been used as a tease riddle for quite some time. "What happens when an unstoppable object meets an unstoppable force?" Turns out this hypothetical phenomenon is called the "irresistable force paradox.

So now I must wonder... where did the Nolan brothers (who wrote the Dark Knight) crib that line from? Are they Hulkamania fans? Pulp fans? Did they come across it as a riddle in a newspaper in 1980s? Physics class?

Or perhaps, the better question is what DOES happen when an unstoppable force meets an immovable object? Do they shake hands? Does unstoppable buy immovable a beer? A cranberry juice? Does unstoppable bodyslam immovable to the mat and drop the atomic big leg on his big hairy chest? Does he string him up and let the police cart him off to Arkham Asylum? Does the universe collapse on itself? Do elephants fly? Do I suddenly become well-paid and really cool?

It's a question that raises countless more questions, but I think pop culture has taught us that unstoppable force often is the victor.