At the end of last month, the Navy got an early Valentine's Day present in the form of a prototype fully-weaponized naval railgun. And on Tuesday, it released a video of its first shot, which we're officially filing under "things not to get in the way of."

The U.S. Army has been very pleased with its fancy new XM25s, the gun that can shoot "smart" bullets at enemies behind cover. But the XM25's bullets are only smart in one dimension, while Sandia National Labs has just tested a prototype laser-guided bullet that can steer itself and home in on targets.

The XM25 is a $35,000 weapon that fires tiny little 25 millimeter grenades up to 500 yards. But these aren't just any microgrenades: they're smart microgrenades that can penetrate heavy cover and then explode when they're on the other side.

Who seriously needs knife cufflinks? I can think of a few guys, Tony Stark, Bruce Wayne or James Bond might find them handy. These stainless steel shirt decorations aren't just for looks, they're deadly enough to take your eyeballs out.