Have you ever seen an insect with an upset stomach, or running a high fever? Probably not. But why is that, other than the fact that you're too busy squashing them to notice? It turns out that some insects have wings covered in nano-scale spikes that naturally tear bacteria to pieces.
Studying the clanger cicada, biophysicists discovered hexagonal arrays of microscopic nano-scale blunt spikes covering the surface of their wings. And when bacterium lands on these surfaces, it has a natural tendency to flow into the valleys between these spikes, which stretches its outer layer until it tears and dies. Similar to how an over-filled plastic bag will stretch thin until it eventually ruptures.
And besides providing more proof that our insect brethren will probably outlive us all, the same techniques could be used to create microscopic nano-spike coatings for public surfaces like doorknobs or railings that would automatically eradicate bacteria without the need for harmful chemicals. [Nature via Popular Science]