4:20   What if a glass of water were LITERALLY half empty? 3:52   What if everyone jumped at once? 2:48   What if the Moon were made entirely of electrons? 3:56   What if you built a billion-story building? 4:35   What if Earth suddenly stopped spinning? 6:47   What if the Earth rotated 90 degrees? 4:02   But what if we tried MORE power? 2:53   What if you used a flamethrower as a snowblower? 4:23   Would a Submarine Work as a Spaceship? 3:28   What if we aimed the Hubble Telescope at Earth? 3:29   Could you survive a nanosecond on the Sun? 2:46   What if the wise men kept walking after Jesus’s birth? 3:47   What if all the lightning on Earth struck the same place at once? 3:41   What if the moon turned into a black hole? 2:58   What if you literally had all the money in the world? 3:55   How to Build a Lava Moat (with xkcd) 3:15   What if you threw a baseball at nearly light speed? 3:06   Could you make an umbrella out of lasers? 3:12   What if the sun suddenly went out?