Automated transport systems/Delivery drones
Such flying robots are often developed for military and surveillance applications, but have great potential when applied to the problem of delivering packages. MatterNet is a startup company working on making this a reality. They are focused especially in regions with inadequate roads. The MatterNet Vision video explains more.
Combined with automated logistics software to control the robots, this could create a delivery service that operates almost invisibly, without noise or congestion, uses a tiny amount of energy (solar-powered charging stations could readily meet the energy needs of the drones) and no labour at all.