Bill Gates thinks big.

His charitable foundation has poured $1 billion into the fight against that great scourge of humankind, malaria, resulting in the creation of a new vaccine that is 100% effective in mice, and is now headed towards trials in humans. If successful, Gates' efforts have the potential to save millions of lives. Gates has also turned his attention to another great scourge of humankind, the hurricane. In a 2008 patent filing that recently came to light, Bill Gates and his friends presented a scheme for reducing the strength of hurricanes by cooling sea surface temperatures, using a fleet of ships that bring up cold water from the depths. Can Gates really pull this off? I don't think so. The obstacles are fourfold: technical, financial, environmental, and legal.