A team of researchers at New York University have created an ultra-light metal that actually floats in water. The applications are, not surprisingly, almost limitless.
The metal itself is technically a syntactic foam, comprised of a magnesium alloy with hollow silicon carbide spheres. As Gizmodo notes, it's a lot like "metallic Swiss cheese." What makes this stuff so unique when compared to pretty much every other metal in existence is the fact that it's slightly lighter than water, while also (allegedly) able to handle a pressure level of 25,000 pounds per square inch.
For those wondering, that's comparable to the pressure at about one mile deep in the ocean. Disclaimer: The concept of creating a syntactic foam has been around since the 1960s, but turning that into a metal is relatively new. That's where the cutting-edge stuff comes in.
In theory, a boat built of this stuff would technically weigh less than water, meaning you could get even more creative with ship design, since you don't have to worry about making sure there's enough water displaced for the ship to float. Things will obviously get heavier once you add people and equipment, but still — this could be an awesome breakthrough.
The project's materials scientist Nikhil Gupta said the material should be production-ready within about three years, and he anticipates some Navy concept ships to be shown off at about that time.