Betsy Mason, at Wired's MapLab blog writes:
This map shows the paths of every hurricane and cyclone detected since 1842. Nearly 12,000 tropical cyclones have been tracked and recorded, and the National Oceanic and Atmospheric Administration keeps them all in a single database. Long-term datasets can be really interesting and scientifically valuable, and this one is undoubtedly both. The map is fascinating. Check it out.