For 25 years, the optical fiber was little more than a fancy telephone wire, but manufacturing engineers, materials researchers and military scientists around the world are starting to turn up the heat and pressure. In recent months and years, optical fiber has found itself laughing at danger in combustion chambers, ceramic manufacturing ovens, and guided missiles. If you think these applications sound too dangerous for photonics, then optical fibers are tougher than you think. Today's fibers are the result of 15 years of developing optical fibers for sensing and measurement in vehicle guidance systems, position and proximity detection, characterization of advanced materials and structures, industrial process control and biomedical systems.