Need inspiration? Follow that octopus. They’ve already inspired invisibility cloak technology and comfortable medical implants - and now innovative small boat propulsion systems. German engineers have mimicked the way octopi evade predators - taking in water and shooting it out the other end using a hydraulic piston to contract cables in place of a muscle. It’s quiet, safe and, unlike propellers, fish can’t get caught in it. The future of marine propulsion? It’s been around for millennia, reminding us that solutions are all around us if we look.