Scenario: Alien Invasion
Overview: The question of whether or not there is other life in the universe has been answered. In spades. Their giant, 15 mile-wide metallic emissaries of death are perched above every major city on the planet just waiting for the word from the mother ship to unleash fiery death upon humanity. And all the puppies, too! Checkmate.
Pros: Justification of the SETI program.
Cons: Anal probes.
Reality Check: Stop with the nonsense. If an advanced civilization somehow manages to make it to earth, it ain't gonna be with giant mother ships made of anything remotely resembling metal. Forget the impossible physics behind it, it's just so hack. No, sorry, there isn't going to be any dog fighting between advanced alien ships and drunken cropdusters. Yeah, that's right, I'm talking to you, "Independence Day." The only way that movie would be plausible is if it is revealed that the aliens are actually a bunch of rebellious alien junior-high school kids who took grampa's old clunker out for an unsupervised joyride and ended up in our neck of the woods.
Can we stop it: No. If they come, that means they didn't destroy each other in their early industrial period. If they're still assholes despite having achieved such a high technological state, I'm sure they would have a little switch that would simply turn our brains off. Assholes.
Rating: 1/10. NaNu NaNu.