When I am an adult, the technology of mankind will undoubtedly have advanced considerably. Cars, buildings, and even people will have adapted to their surroundings in incredible ways.
Though my fantasy city will be underwater, breathing will not be a problem as the oxygen taken in by the plants on the outside shall be transferred to the areas below. In addition, this air can then be released to the surface of the water, creating energy in the process. Also, vehicles will have mastered the art of flight. To keep traffic under control, lights shall be installed to manage the chaos in the air. Furthermore, life will be made much easier with the incorporation of movable working spaces where your entire desk, chair, computer and other necessities will be kept in a small room with a potential – similar to vehicles – of flight. When one finished his or her work for the day they would simply need to direct their office toward home. These chambers would also allow many to work from home and would provide easy transportation. They could also be stacked efficiently in the daytime to save space.
I imagine many things. I imagine that there shall be an underwater city, inside a dome, complete with a picturesque skyline against the blue. I imagine that teleportation shall be possible, as will the ability to fly a car. I imagine that you will be able to take your office home with you. I imagine that Hong Kong will be an even better place.