xkcd's What If?

If all humans died, when would the last light go out?

What would a magnitude 15 earthquake be like?

Could you survive a nanosecond on the Sun?

What if everyone pointed a laser at the moon?

What If Earth Grew 1cm Every Second?

What if you funneled Niagara Falls through a straw?

What if a glass of water were LITERALLY half empty?

What if NASCAR had no rules?

Would a Submarine Work as a Spaceship?

What if we aimed the Hubble Telescope at Earth?