Nifty! I liked his comparison of the speed of the beam of light with that of a bullet. The video of the beam of light going through the coke bottle lasted a few second. If we were to watch the video of a bullet travelling the same distance at the same camera speed, the video would last 1 year. Wow, that gives you perspective!
Crusading Chameleon likes the size of this ad:
A rocket mass heater is the most sustainable way to heat a conventional home