Planetary rovers can already find potential signs of life, but they're not really meant to find life itself. NASA may have just the device to find that concrete evidence, though. Its newly tested Chemical Laptop is the first device built to detect amino acids and fatty acids (the telltale signs of life as we know it) on other worlds such as Mars.
The battery-powered device needs liquid samples to work, but it has a coffee machine-like mechanism that uses hot water to get the organic material out. Any practical exploratory uses are years away given that the next Martian rover won't touch down until 2021, and landings on other celestial bodies (such as Jupiter's moon Europa, or Saturn's Enceladus) would be even more distant.
However, the Chemical Laptop wouldn't go to waste here on Earth: it could help with in-the-field environmental tests, or bust companies peddling counterfeit drugs. And even if it doesn't find any short-term uses, it might pay off if it delivers the smoking gun evidence that humans aren't alone.