Interesting write-up on New Scientist about d3o, "A futuristic flexible material that instantly hardens into armour upon impact will protect US and Canadian skiers from injury on the slalom runs at this year's Winter Olympics." What's interesting is that this is a response to stimulus at a molecular level, or at least at the level of the chemical bonds between molecules. Lots of intriguing applications suggest themselves, not least the "flexible ballistic protection" that the article mentions. Hmmm.