Quite a simple game, you ask a hypothetical 'What if...?' question, and the person below you comes up with the best silly answer they can give.

Example:
Poster 1: What if the world was flat?
Poster 2: Cockroaches would have an even better chance of survival.
What if six times nine equaled forty two?
Poster 3: You wouldn't have made a reference. And the universe would have been replaced with a stranger one.
What if you were a turtle?

To start the game off:

What if the Earth's topography, by some twist of physics, became inverted?

Total annihilation of almost all non-aquatic life (as well as most aquatic life), as the oceans rush from the new mountains into the new depths. Only the Netherlands survive.

What if weeks had nine days instead of seven?

American companies would exploit the production of workers even moreso than they already do.

What if we drove on driveways and parked on parkways?

Amateur comedians would have to find different material.

What if chocolate was highly nutritious?

Then finally chocolate chip pancakes would be part of a balanced breakfast.

What if humans laid eggs instead of giving live birth?

~SE++

People would feel differently about eating eggs for breakfast. We would eat baby animals instead. Also, maternity leave would become a thing of the past.

What if people could use their toes like fingers?

Shoe design would have developed differently.

What if the whole "telephone" fad had faded into obscurity ten years after its invention?

We might still know who our neighbors are, and actually invite them over for dinner once in a while.

What if the Radio City Music Hall Rockettes were actually guys?

Then their costumes probably wouldn't show off so much leg.

What if homeopathy actually worked?

Then the trace amounts of arsenic in public water would kill us all.

What if video game based movies were consistently good?

Then Ben Affleck wouldn't have been in Daredevil.

What if the United States of America was a Socialist county?

~SE++

Not much would change honestly.

What if everybody lived to be 100, that is exactly 100 years old?

It'd be easier to make funeral arrangements, though birthdays would be a little sadder.

What if the entire world was a single race and spoke a single language?

~SE++

We would have to come up with a more creative means for discrimination. Although, I imagine that in that scenario different nations would make a great effort to set themselves apart, so it wouldn't be that hard. Nationalism and religion would probably be the major dividing lines.

What if chocolate were good for you?

Then I wouldn't have posted that same question a week ago.

What if trees could speak?

It still wouldn't stop the lumberjacks because they already wear earmuffs to cut out the chainsaw noise.

What if doughnuts cured cancer?

Then cops would never get cancer

What if there where no what if questions?

Then we would have to rename the thread "Perchance Should..."*

What if all physical damage done to the human body took a couple of hours to set in?

*I think that works anyways

Boxing matches would last much longer.

What if humans could digest wood?

Sawdust would solve world hunger. Mind you, it still doesn't have a lot of vitamins, but if you could eat it, it would fill you up.

What if people dressed up on every day except Halloween?