Lehigh University

The promise of reusable sticky things, from Post-it Notes to Blu Tack, has never quite been fulfilled. They're just never quite as sticky the second time around, or the third. But now, a team of engineers thinks it has an answer, inspired by one of nature's great stickers, the humble, slimy snail.

​Owls are known for their near-silent flight, which allows them to swoop down on prey unheard. Wind turbines, though, are often accused of being too noisy. Scientists are addressing the one situation with the other, by copying the structure of owl feathers to make turbine blades more quiet.