The 2003 German Year of Chemistry has produced some gem-like finds. Ingenious heat-store microcapsules from BASF can be used in building materials to keep room temperature constant. The plastic capsules, 6-10 micrometres in diameter, are filled with a liquid such as paraffin and, when integrated into interior plasterboard or render, act as latent heat stores. When the contents melt, heat is absorbed to cool the room; when they solidify, heat is given off and room temperature rises. Visit www. basf. com to find out more.