This March marked 10 years since the Tohoku earthquake triggered a devastating tsunami off the northeast coast of Japan. Major tsunamis are rare throughout history, but it's often impossible to know exactly when and where one will occur. But to improve warning, the thousands of cargo ships that traverse the world's oceans could offer critical, if unexpected, assistance. While ferrying goods, commercial vessels could leverage their GPS systems to form a distributed network of sensors capable of picking up subtle elevation changes indicative of a passing tsunami, a series of large waves most often caused by earthquakes under the sea. This approach, which researchers simulated in a recently published paper, aims to significantly enhance detection and forecast abilities by simply turning existing ships into a floating array for sensing waves, all without having to spend a lot of money on new infrastructure.