What If We Are Not the First Technologically Advanced Civilization on Earth?
https://www.youtube.com/watch?v=wlEJZwevXqg

What If You Had One Hundred Billion Dollars
https://www.youtube.com/watch?v=SIhwVysyi6I

What If the Earth Was Tidally Locked to the Sun?
https://www.youtube.com/watch?v=fVc6S15TFK8

What If Money Didn't Exist?
https://www.youtube.com/watch?v=DHho8Pa0O6I

What If You Had To Repopulate The Planet?
https://www.youtube.com/watch?v=W_mxyHXgB-A