OK, I just had this idea, and figured that I should write it down.
Imagine that, as we go forward in time, the internet gets bigger and deeper and more complex and so on. Imagine that we get into a cyberpunk-style scenario where we actually dive into the internet, and perhaps cyberspace is a wholly different experience, rather than perfectly emulating real life. Now, imagine the sort of plot point where things happen such that we're all in the internet, unable to get out, and, eventually, the people of Earth don't even realize that we're inside of an internet. Instead, that's our world.
Now, imagine that that's what has already happened. The crazy idea is this: Our world is the simulation within the first incarnatiion of something cyberspace-like. It has its own laws and everything, so whatever we do - including making the internet - works within the simulation. Frak, for all that we know, it's happened more than once before. This is also essentially a version of the brain-in-a-jar scenario of philosophy and, as such, can neither be proven true nor be proven false. Of course, like with those situations, it really doesn't matter whether it's true, since we're not in a position to do anything about it, anyway, since we're restricted to behaving within the confines of the simulation.
That's my crazy idea.