The United States Navy has a gun that's this week reached a milestone, but before we discuss that, you've got to know that is works with more kinetic energy than a one-ton vehicle moving at 100 miles per hour. This week they've fired the gun for the 1,000th time, this marking a point quite close to production and real-world deployment. Though we've been using railguns in first person shooter video games for some time now, they've only been theoretically possible until very recently - and starting very soon, they'll be in use by the United States armed forces.
Right now researchers at the Naval Research Labs Charged Particle Physics branch are "firing up to 15 shots per week on the laboratory's experimental railgun, researchers at NRL perform detailed testing and analysis of rails and armatures, providing S&T expertise to the Navy program that is directly applicable to tests at large-scale power levels" - this noted by Dr. Robert Meger, head of the Naval Research Labs' Charged Particle Physics branch. Only a couple shots a day, but each shot represents another step towards a final approved for use product.
What you've got here is a gun which uses an electromagnetic current to make the bullet fly out of the gun. The bullet is non-explosive, mind you, and it's fired at several times the speed of sound. The bullet doesn't have explosives as a traditional bullet would, instead relying entirely on kinetic energy. This gun has been enhanced to be approximately 1.5 megajoules of energy strong, this comparable, again, to more than a one-ton vehicle moving at 100 mph.
The gun remains in testing now, but as the Senate Armed Services Committee voted this past April to defund such projects (though they failed,) the future of the device remains in question. NRL Commanding Officer Captian Paul Stewart noted the following on the project: "A railgun weapons system must be able to launch hundreds of projectiles and withstand extreme pressures, currents and temperatures. [This landmark shot] demonstrates Navy researchers are steadily progressing toward achieving that goal, developing a more effective and efficient future ship combat system."