Back before the Internet, media was relatively simple. There were relatively few voices in the media fighting for our attention and, for the most part, they all said about the same thing. Music stars became superstars because fewer bands were in the public eye. Movie stars became superstars because consumers didn’t have access to lesser known “indie” content.
As such, the possibilities of science fiction storytelling were distilled through a relatively small number of voices. This led to the broadly held conclusion that Star Trek basically invented our scientific present.  The idea that the popular television show from the 1960s was the very rudder of science for the next forty years is a fascinating one. We all want to see holodecks so we can live out our fantasies; we all want transporters so we can get where we’re going more quickly; we all want food replicators so we can feed the poor; we want powerful sensors (manifested today in the form of GPS tracking) that can get us where we need to go with ease; we all want warp drive because it would make everything outside our windshield look like the coolest screen saver ever.
But now the web has a stranglehold on the popular consciousness, especially in the world of science; and the most popular expression of science fiction nowadays is, take it or leave it, video games. Violent scifi video games like Halo and Mass Effect offer gamers the opportunity to behold other worlds, view inventions of the future, and then to blow them to shreds using weapons only found in our dreams.
One of those dreams is the rail gun. It’s a weapon that shoots a projectile not with gunpowder, but with electromagnetic power. The projectile is as powerful as a grenade launcher, and has been known to blow alien bad guys into tiny chunks.
Now, yesterday’s Star Trek is today’s Halo. Now, it’s Halo’s turn to come true. The United States Navy has invented a rail gun, which vomits projectiles well over 5,000 miles per hour, potentially shredding targets, a form of no-recoil artillery that may prove fearsome on the battlefield.
Okay, all that’s awesome, but what does it have to do with GPS? The answer is that the Navy’s getting creative: they’ve put the call out to defense contractors to design rail gun projectiles that can be guided by GPS. Whether this will change weapons technology forever has yet to be determined. However, these guns may be effective should that alien invasion come to pass.