Here's a quick science video from Dr. Phil Plait.

I'm sure you remember the infamous and viral Double Rainbow You Tube video. Well, here is Phil's take on rainbows with an added twist (so to speak).

It's about polarization, how light gets polarized, and how that relates to rainbows. It's quick, it's educational, and it's nowhere near as annoying as that Double Rainbow guy.

Here's a link to Phil's Bad Astronomy Blog that explains how this works.