Stranger Theories

If it somehow turned out that the earth was flat (like certain conspiratorial persons claim to be the case), then that fact would be completely unimportant.
It would just be a minor detail - because in that case everything we think we know would be wrong - including things far more important than the shape of the earth.
The easiest way the earth could be something radically other than a sphere would be if it didn't exist at all, except for the small part you can see right now.
And that part would be flat. This is a Boltzmann Brain situation, we're talking hardcore solipsism here.

How Scientology could be somewhat true:
What if the physical universe we live in is not "bottom up"?
That means reductionism would be false. Reality is not created from the simplest possible particles combined into more complex particles.
What if physical reality is created from the "middle"? Both higher and lower complexity levels would originate from the level also occupied by human minds.

Science fiction stories are full of what should be profoundly interesting events, but I think they often still feel boring.
Reality is just the opposite: nothing interesting ever happens, but it's still more meaningful than we can know.