> The result is a surface full of needles that are 2 nanometers thick – 30,000 times thinner than a human hair – and 290 nanometers high. Ooh. That's right aro

> The result is a surface full of needles that are 2 nanometers thick – 30,000 times thinner than a human hair – and 290 nanometers high. Ooh. That's right around the correct range for structural colouration. You could draw designs with this, or utilitarian colour-coding. Red (700nm) means danger— The spikes will get bacteria, but are too big for viruses.