CWmike writes "As the deadly tsunami generated by Friday's massive earthquake off the coast of Japan headed toward the United States, scientists at NOAA's Center for Tsunami Research tracked its progress in real-time. Dozens of deep-ocean tsunami-monitoring sensors more than three miles beneath the surface of the Pacific Ocean picked up information on the silent swell of water and transmitted it by way of a satellite to the Pacific Marine Environmental Laboratory in Seattle, Wash. Here, scientists crunched the data and quickly developed real-time predictions about how and when the tsunami would reach select locations in Hawaii, Alaska and the US west coast. The models predicted the wave arrival time, estimated wave height and the likely extent of inundation for about 50 communities likely to be affected."Another piece of useful infrastructure: reader JustABlitheringIdiot writes "Google has launched a version of its Person Finder service for people caught up in the Japanese earthquake. The website acts as a directory and message board so people can look for lost loved ones or post a note saying they are safe."