“Inventor and programmer” Robert Walker at Science 2.0 discusses the vast resources of our solar system: Asteroid Resources Could Create Space Habs For Trillions; Land Area Of A Thousand Earths.

This leads him in turn to talk about the Fermi Paradox and possible solutions to it: With Humans Already Close To Space Colonization – Why Haven’t Millions Of Years Old ETs Colonised Our Solar System Already?

I liked this video he used: