When bombardier beetles are attacked, they mix chemicals in their body to create a rapid and violent reaction, squirting outa concoction that's corrosive and hot,near the boiling point of water. Inspired by thisdefense mechanism,Swiss engineers have created a polymer-based material that gives offsteam and foam if it is tampered with. The materialconsists of sheets of polymer between which two different chemicals are sandwiched, including hydrogen peroxide. They areseparated by a rigid wall that breaks upon forced entry, after which the materials react in a most unpleasant manner.

Pretty much every chemist worth his or her salt knows the Merck Index. First published in 1889, the Merck Index is an enormous compendium of chemicals, their physical properties and their industrial uses. Its genesis as a collection of medicinal chemicals is still apparent today, and many of the compounds therein are useful in pharmaceutical production or are finished pharmaceuticals themselves. Way back in the mists of time when I was at university and doing a summer internship, my friends and I used to take bets over who could find the deadliest or gnarliest chemicals in the Merck Index, or who could find the chemical with the most carbons or chiral centers - basically anything to pass the time while I was waiting for the gel electrophoresis to finish doing its thing. The Merck Index saved my sanity that summer and won me some bragging rights (and about $5 total).