Five years ago, when Pete Roos and Randy Reibel co-founded Bridger Photonics, a laser-engineering firm, methamphetamine was a huge problem in their home state of Montana. At the time, half of all state inmates had been incarcerated for meth-related crimes. Shortly after launching the company, Roos, who has a Ph.D. in laser physics, began work on a hand-held laser device to help police officers find meth labs. Producing methamphetamine gives off toxic fumes, and Bridger's laser technology, which is still in development, detects these gases by measuring the amount of light absorbed by the gas molecules. Biotech firms have also begun using lasers from Bridger Photonics to analyze cells and tissue during clinical trials. Roos says he likes working on projects that benefit society. "That's what motivates us," he says.