- What If Everyone Froze for 1,000 Years?
- What If We Built an O'Neill Cylinder?
- Discussed: What If We Lived in Space? - With Dr. Ronke Olabisi
- What If You Caught the Swine Flu?
- What If a Massive Locust Swarm Attacked Your City?
- What If Everyone Stopped Cutting Their Hair?
- What If Oceans Were Liquid Mercury?
- What If Your Brain Were Twice the Size?
- Discussed: What If Your Brain Were Twice its Size? with Michio Kaku
- What If Every Satellite Fell to Earth?
- What If Jupiter Swallowed Earth?