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"
The short answer is "no", but it is a qualified "no" because there are odd ways of interpreting the question which could justify the answer "yes". Light is composed of photons so we could ask if the photon has mass. The answer is then definitely "no": The photon is a massless particle. According to theory it has energy and momentum but no mass and this is confirmed by experiment to within strict limits. Even before it was known that light is composed of photons it was known that light carries momentum and will exert a pressure on a surface. This is not evidence that it has mass since momentum can exist without mass. [ For details see the Physics FAQ article What is the mass of the photon? ]. Sometimes people like to say that the photon does have mass because a photon has energy E = hf where h is Planck's constant and f is the frequency of the photon. Energy, they say, is equivalent to mass according to Einstein's famous formula E = m...
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