blowing stuff up

Without a doubt, the most fun thing I've worked on in my five-plus years at PopSci is the Gray Matter column. Nearly every month since mid-2002, contributor Theo Gray has come up with new ways to illuminate the world of elemental chemistry, often by setting things on fire. But far from your average YouTube-loitering pyromaniac, Gray combines sharp, lively writing with a gifted professor's knack for making the complex simple.

Turn up your sound and chemist Gerard Harbison will explain it all. The tiny white thing sitting in front of the orange water balloon contains a mere 1/60th of an ounce of triacetone triperoxide (TATP), the chosen detonator of would-be shoe bomber Richard Reid. (Note: TATP is still explosive when it's wet, so it's probably one of the reasons for the TSA's draconian rules about liquids.)

Add a 9-volt battery and KABOOM.

But there's good news.