The latest episode was about the nanoarchitecture of butterfly wings, which is a fascinating topic.
A researcher mimicked the nano structure onto a piece of metal, a disk the size of a nickel, which is so hydrophobic that two disks close to each other would float, as it had essentially a bubble trapped between them.
The subtext of the show was about "combating climate change". So the narrator ludicrously suggests that it could be used to create floating cities because global water levels are rising.