Drones are already capable of many things for us. As the below video shows, they could be used to build a rope bridge capable of supporting the crossing of a person. These quadrocopters built a rope bridge that spans 7.4 meters and has 9 rope segments. The rope is made out of Dyneema.
Federico Augugliaro, Ammar Mirjan, Fabio Gramazio, Matthias Kohler, and Raffaello D’Andrea are the researchers behind this project. More information is available here.