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.
A start-up company called TacoCopter have envisioned a more whimsical application of the technology. They want to allow people to order tacos on their smartphone at at any hour of the day or night and have them delivered by autonomous drones.
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.