Great movie-plot threat:
Financial institutions depend on timing that is accurate to the microsecond on a global scale so that stock exchanges in, say, London and New York are perfectly synchronised. One of the main ways of doing this is through GPS, and major financial institutions will have a GPS antenna on their main buildings. “They are always visible because they need a clear view of the sky,” Humphreys told Wired.co.uk.
He explains that someone who directed a spoofer towards the antenna could cause two different problems which could have a major impact on the largely automated high-frequency trading systems. The first is simply causing confusion by manipulating the times—a process called “time sabotage”—on one of the global stock exchanges. This sort of confusion can be very damaging.