An anonymous reader writes to mention an article on NetworkWorld about a free software application that detects Tsunamis
by listening for vibrations in the hard drives of computers. The peer-to-peer network uses the technology that allows HDDs to keep read-write heads on track, and passes the information to a network for analysis. From the article: "If an earthquake that could lead to a tsunami is detected, the supernodes inform the other nodes. Computers running the client software and connected to the peer-to-peer network can then warn of such events. The software is able to provide such warnings because the seismic waves produced by earthquakes travel at about 5,000 kilometers per hour, while tsunamis move much slower at 500 to 1,000 kilometers per hour"