Carbon nanotubes are some of the strongest and stiffest materials known, while being at the same time very light. They consist of carbon cylinders of just one atom thickness. If used within composite materials they would massively enhance the strength of an object resulting in super strong alloy.
18th-century Persian-forged Damascus steel sword. ( Rahil Alipour Ata Abadi/wikimedia )
In 2006, researchers discovered that the people of Damascus were able to mix nanotubes in their steel hundreds of years ago. Resulting in beautiful blades covered by swirling patterns and, more importantly for the soldiers of the time, exceptionally durable and the razor-sharp edges. We now know the exact composition of Damascus steel, yet modern metallurgists have failed to reproduce it so far.