The Guardian »

Self-healing concrete, which is produced by mixing limestone-producing bacteria with concrete, has been developed by microbiologist Hendrik Jonkers. The bacteria live in the concrete for 200 years and is activated by rainwater or atmospheric moisture. Initially used for the preservation of monuments, the self-healing concrete is now commercially available for the repair of small cracks on existing structures. The self-healing concrete was used in the construction of a canal and irrigation system in Ecuador.