By manipulating materials at the atomic scale, scientists from the University of Pennsylvania's School of Engineering and Applied Science, the University of Illinois at Urbana–Champaign, and the University of Cambridge claim to have created a sheet of nickel that is as strong as titanium, but up to five times lighter.
Strong as steel is a cliché, but it's one that's true. Steel is so strong and so affordable that it's hard for the average person to go through their day without seeing tons of it in the form of bridges, vehicles, building supports, and reinforced concrete, just to name a very few examples.
However, steel and other metals that we use on an everyday basis aren't anywhere near as strong as they could be. The crystalline structure that make up metals like steel, aluminum, and titanium give them their strength and flexibility, but this structure is imperfect, so the forces applied to the metals under stress cause the atoms in them to slip and the structure to fail far below the metal's theoretical strength limit. Titanium, for example, would be 10 times stronger if it had an ideal structure.