An invention in the works. Monowire is, in theory, a mono-molecular strand that is incredibly strong. It is, in practice a little wider, but effectively only a few molocules wide.

So what, you may ask? Just think for a second: How sharp is the average knife -- in measurement of molecules? Probably somewhere near a few thousand (if anyone can get actual figures on this, I'm more than open to being corrected, it's just a guess). That means an invisible strand of wire that can cut through most any known substance. There are some pretty shady applications of such a technology, but many very useful ones too. Smoother cuts than lasers or water jets, and it will never need sharpened.

The only problem is, it's still pretty much science fiction. A popular item in many cyberpunk games and movies, current science hasn't made anything quite so useful, or deadly. Currently, scientists have only made monowire shorter than a millimeter (much shorter), so there's no practical applications to it, but after they get it to lengths of centimeters, it will be useful for cutting ANY small objects, including diamonds.