The researchers at Caltech wanted to make superhydrophobic materials for practical applications. These kind of applications can be for example to have container ships glide more smoothly through the water. so they showed water droplets on these nanotubes at different velocities to see what kind of impact they have, whether they break into a couple of separate drops or whether they make a larger spray. Then they changed the angle and the shape of the nanoarray to make a really cool half pipe. Watch to see what happens when two drops go on the half pipe.
Original article featured in Popsci: